1 00:00:00,090 --> 00:00:02,490 The following content is provided under a Creative 2 00:00:02,490 --> 00:00:04,059 Commons license. 3 00:00:04,059 --> 00:00:06,330 Your support will help MIT OpenCourseWare 4 00:00:06,330 --> 00:00:10,720 continue to offer high quality educational resources for free. 5 00:00:10,720 --> 00:00:13,350 To make a donation or view additional materials 6 00:00:13,350 --> 00:00:17,290 from hundreds of MIT courses, visit MIT OpenCourseWare 7 00:00:17,290 --> 00:00:18,480 at ocw.mit.edu. 8 00:00:27,157 --> 00:00:28,740 ROBERT TOWNSEND: So today, we're going 9 00:00:28,740 --> 00:00:32,259 to talk about labor and development. 10 00:00:32,259 --> 00:00:35,130 There are several pieces to this, 11 00:00:35,130 --> 00:00:42,840 just to sort of get into it. 12 00:00:42,840 --> 00:00:47,160 One, number one, back to risk sharing, full benchmark, 13 00:00:47,160 --> 00:00:51,240 but this time with endogenous labor supply and wage risk. 14 00:00:51,240 --> 00:00:55,470 And I'll mention sort of some tests using that framework. 15 00:00:55,470 --> 00:00:57,330 I dumped a lot of the excess slides, 16 00:00:57,330 --> 00:01:00,090 because I don't want that to be the sole focus of the lecture 17 00:01:00,090 --> 00:01:03,990 today, although it's kind of the obvious starting point. 18 00:01:03,990 --> 00:01:10,440 With those lotteries, basically, you 19 00:01:10,440 --> 00:01:14,460 end up dealing with a non-convexity. 20 00:01:14,460 --> 00:01:23,070 And then that has a lot to do with estimating elasticities 21 00:01:23,070 --> 00:01:25,350 of labor supply from micro data versus what 22 00:01:25,350 --> 00:01:27,570 you see in aggregate data. 23 00:01:27,570 --> 00:01:29,430 And we've learned a lot about that. 24 00:01:29,430 --> 00:01:32,430 So there is sort of the complete market's version. 25 00:01:32,430 --> 00:01:36,000 And then, a la lecture last time, the incomplete market's 26 00:01:36,000 --> 00:01:41,660 version, where the aggregate elasticity is higher, sometimes 27 00:01:41,660 --> 00:01:45,770 a lot higher, than it is in the micro data for reasons 28 00:01:45,770 --> 00:01:47,660 of the aggregation. 29 00:01:51,000 --> 00:01:53,730 And since we've talked about zoom in, zoom out, 30 00:01:53,730 --> 00:01:57,420 you know, micro, macro, that seems like a relevant thing. 31 00:01:57,420 --> 00:02:02,110 And then we, in fact, end the lecture with Seema's, 32 00:02:02,110 --> 00:02:04,570 Jayachandran, paper on labor supply. 33 00:02:04,570 --> 00:02:07,680 And I think it was India, with rainfall 34 00:02:07,680 --> 00:02:08,870 and agricultural shock. 35 00:02:08,870 --> 00:02:18,420 So sharing wage risk, I just said this. 36 00:02:18,420 --> 00:02:22,740 We have non-labor income, which is like the y moving around 37 00:02:22,740 --> 00:02:23,580 we've had before. 38 00:02:23,580 --> 00:02:25,740 But we also have income from wages, 39 00:02:25,740 --> 00:02:27,840 but hours are endogenous. 40 00:02:27,840 --> 00:02:30,110 Labor is not supplied inelastically. 41 00:02:30,110 --> 00:02:38,470 And we're going to allow for heterogeneity among individuals 42 00:02:38,470 --> 00:02:42,610 in a household and heterogeneity across households. 43 00:02:42,610 --> 00:02:44,440 So let me just lead off with an example, 44 00:02:44,440 --> 00:02:46,790 because I think it makes the points pretty well. 45 00:02:46,790 --> 00:02:49,630 And then we'll generalize. 46 00:02:49,630 --> 00:02:53,710 So you have two people, or two households. 47 00:02:53,710 --> 00:02:56,260 One is risk neutral. 48 00:02:56,260 --> 00:02:59,420 The other risk averse. 49 00:02:59,420 --> 00:03:00,920 Why is this an obvious example? 50 00:03:00,920 --> 00:03:04,970 Because the risk neutral guy should absorb all the risk 51 00:03:04,970 --> 00:03:10,040 and would in every setup that we've seen so far 52 00:03:10,040 --> 00:03:11,840 and take it away from the risk averse 53 00:03:11,840 --> 00:03:14,390 guy, who's got a strictly concave utility function. 54 00:03:14,390 --> 00:03:18,380 However, this guy cares about leisure and consumption, not 55 00:03:18,380 --> 00:03:20,730 just consumption. 56 00:03:20,730 --> 00:03:23,160 So typical Cobb-Douglas specification 57 00:03:23,160 --> 00:03:27,695 with some curvature, making him strictly concave guy. 58 00:03:30,510 --> 00:03:36,060 If you don't consume leisure in your work, that's supplied. 59 00:03:36,060 --> 00:03:39,588 You get this wage, W2. 60 00:03:39,588 --> 00:03:41,880 When we generalize, we're going to allow different wage 61 00:03:41,880 --> 00:03:46,920 processes for different people, not modeling necessarily 62 00:03:46,920 --> 00:03:48,660 why they have different talent. 63 00:03:48,660 --> 00:03:52,530 But for now, there's only one guy supplying labor. 64 00:03:52,530 --> 00:03:54,540 Again, y is this non-labor income. 65 00:03:54,540 --> 00:03:57,000 T is the time endowment. 66 00:03:57,000 --> 00:03:59,100 Consumption good is the numeraire. 67 00:03:59,100 --> 00:04:01,770 Wages are real. 68 00:04:01,770 --> 00:04:04,860 And there is a budget constraint for this two-person programming 69 00:04:04,860 --> 00:04:12,560 problem, which is like a small open economy in the sense 70 00:04:12,560 --> 00:04:16,070 that it's partial equilibrium, and they 71 00:04:16,070 --> 00:04:17,810 face these outside wages. 72 00:04:17,810 --> 00:04:20,060 In fact, these wages may be moving around. 73 00:04:20,060 --> 00:04:23,960 It could be a village with two people, something like that. 74 00:04:23,960 --> 00:04:27,890 Wages are determined in the district or national level. 75 00:04:27,890 --> 00:04:31,130 This is the standard budget constraint though. 76 00:04:31,130 --> 00:04:35,520 Call this thing full income, if you remember Becker price 77 00:04:35,520 --> 00:04:36,020 theory. 78 00:04:39,150 --> 00:04:42,170 So basically, it's as if you supplied all the time 79 00:04:42,170 --> 00:04:46,880 you have, cap T, hours and days times the wage. 80 00:04:46,880 --> 00:04:49,550 You have this non-labor income. 81 00:04:49,550 --> 00:04:51,210 The community as a whole has this. 82 00:04:51,210 --> 00:04:54,660 And then, you have consumption and Mr. 2 at least 83 00:04:54,660 --> 00:04:56,710 buys back leisure. 84 00:04:56,710 --> 00:04:58,650 You know, well, it's obvious, you could just 85 00:04:58,650 --> 00:05:00,270 take time minus leisure. 86 00:05:00,270 --> 00:05:03,660 That would be labor supply and put it on the right hand side. 87 00:05:03,660 --> 00:05:07,192 But it's kind of useful to talk about leisure as a good, 88 00:05:07,192 --> 00:05:10,950 because that's what enters the utility function. 89 00:05:10,950 --> 00:05:16,950 And we have some standard sort of consumption sharing rules, 90 00:05:16,950 --> 00:05:18,700 division rules. 91 00:05:18,700 --> 00:05:21,520 Who's going to bear the risk? 92 00:05:21,520 --> 00:05:26,780 Well, it's going to turn out that as we've done so far, 93 00:05:26,780 --> 00:05:30,350 this non-labor income risk is going to be shared-- 94 00:05:30,350 --> 00:05:34,400 taken away entirely by household 1. 95 00:05:34,400 --> 00:05:36,350 But things are much more complicated 96 00:05:36,350 --> 00:05:38,150 when it comes to the wage. 97 00:05:38,150 --> 00:05:41,480 The wage moves around, and it changes income. 98 00:05:41,480 --> 00:05:45,170 But the wage also represents a rate 99 00:05:45,170 --> 00:05:47,870 of substitution between consumption and leisure 100 00:05:47,870 --> 00:05:50,750 for the group as a whole, even though person 2 101 00:05:50,750 --> 00:05:52,630 has to supply it. 102 00:05:52,630 --> 00:05:54,410 You know, the wage goes way up, there's 103 00:05:54,410 --> 00:05:57,590 kind of a change to opportunity set for the group. 104 00:05:57,590 --> 00:05:59,870 And you can imagine things should 105 00:05:59,870 --> 00:06:03,485 move in order to be efficient to take that into account. 106 00:06:07,840 --> 00:06:11,010 So we solved the problem in two steps. 107 00:06:11,010 --> 00:06:17,850 And that's also going to make it familiar in the sense of it 108 00:06:17,850 --> 00:06:20,820 integrates with what we've been talking about so far. 109 00:06:20,820 --> 00:06:24,270 First, ex post inefficiency, suppose-- 110 00:06:24,270 --> 00:06:27,700 ex post efficiency-- this is like the second welfare 111 00:06:27,700 --> 00:06:28,200 theorem. 112 00:06:28,200 --> 00:06:30,370 But I'll tell you what I mean. 113 00:06:30,370 --> 00:06:32,710 Any Pareto optimal allocation can 114 00:06:32,710 --> 00:06:37,780 be supported among households with a suitable lump sum 115 00:06:37,780 --> 00:06:39,700 taxes and subsidies. 116 00:06:39,700 --> 00:06:41,730 Remember that theorem? 117 00:06:41,730 --> 00:06:44,040 OK, so what does it mean for us? 118 00:06:44,040 --> 00:06:49,700 You can kind of decentralize the problem of the two people, 119 00:06:49,700 --> 00:06:55,220 as if one or later both can supply labor on their own. 120 00:06:55,220 --> 00:06:57,590 But this lump sum tax or transfer 121 00:06:57,590 --> 00:06:59,540 is like an internal redistribution 122 00:06:59,540 --> 00:07:01,200 within the household. 123 00:07:01,200 --> 00:07:03,590 So for any target Pareto optimal allocation, 124 00:07:03,590 --> 00:07:08,300 you can find a transfer and then have each act in isolation, 125 00:07:08,300 --> 00:07:12,240 maximizing utility. 126 00:07:12,240 --> 00:07:14,980 And then step 2 is to take sort of those indirect utility 127 00:07:14,980 --> 00:07:18,350 functions, take a step back in time 128 00:07:18,350 --> 00:07:21,200 and maximize the ex ante expected utility. 129 00:07:21,200 --> 00:07:24,700 And that's going to look like a standard risk sharing problem. 130 00:07:24,700 --> 00:07:28,610 And in this case, for this baby example, 131 00:07:28,610 --> 00:07:31,880 only member 2 is supplying labor. 132 00:07:31,880 --> 00:07:36,890 Remember it was Cobb-Douglas, and the power was basically 2. 133 00:07:36,890 --> 00:07:40,230 So basically here it's easier. 134 00:07:40,230 --> 00:07:42,530 You take 1/2 of your full income. 135 00:07:42,530 --> 00:07:44,700 And that's your consumption. 136 00:07:44,700 --> 00:07:51,700 So those are those easy kind of consumption expenditure rules. 137 00:07:51,700 --> 00:07:52,900 This is actually the same. 138 00:07:52,900 --> 00:07:54,940 You put the wage over here. 139 00:07:54,940 --> 00:07:59,510 The value of leisure is again 1/2 of your full income. 140 00:07:59,510 --> 00:08:02,050 So those are with that functional 141 00:08:02,050 --> 00:08:06,940 form standard leisure consumption for household 2, 142 00:08:06,940 --> 00:08:10,750 plug it back into the underlying utility function, 143 00:08:10,750 --> 00:08:16,450 raise it to a power, and you may remember working this out 144 00:08:16,450 --> 00:08:18,290 at some point in some other course. 145 00:08:18,290 --> 00:08:20,620 You get a standard indirect utility function 146 00:08:20,620 --> 00:08:29,090 with all this stuff going on in terms of these coefficients. 147 00:08:29,090 --> 00:08:31,910 Well, it's kind of obvious that it had to end up this way. 148 00:08:31,910 --> 00:08:37,730 Note that the wage is in here a couple of times, 149 00:08:37,730 --> 00:08:40,880 partly because the full income and partly 150 00:08:40,880 --> 00:08:43,840 because this guy's optimizing-- 151 00:08:43,840 --> 00:08:49,130 as the wage changed, say, the allocation, 152 00:08:49,130 --> 00:08:52,670 the maximizing allocation would change. 153 00:08:52,670 --> 00:08:54,290 You've got an indifference curve, 154 00:08:54,290 --> 00:08:56,623 and you're going to change the slope of the budget line. 155 00:08:59,770 --> 00:09:04,180 So now we take that step back and consider 156 00:09:04,180 --> 00:09:05,470 the overall maximum. 157 00:09:05,470 --> 00:09:10,750 But instead of having utility of consumption directly of the two 158 00:09:10,750 --> 00:09:14,140 members, we can use the indirect functions. 159 00:09:14,140 --> 00:09:16,810 I mean, if you believed me, then the indirect function 160 00:09:16,810 --> 00:09:19,590 is without any restrictions. 161 00:09:19,590 --> 00:09:25,080 It's a natural object that represents efficient ex post 162 00:09:25,080 --> 00:09:25,980 optimization. 163 00:09:29,700 --> 00:09:31,730 Here's that row. 164 00:09:31,730 --> 00:09:35,250 Did I-- I should have emphasized it. 165 00:09:35,250 --> 00:09:39,390 Row is the amount that say 2 is getting from 1. 166 00:09:39,390 --> 00:09:41,700 Those are the internal transfers. 167 00:09:41,700 --> 00:09:46,650 And household 2 optimizes for a given row. 168 00:09:46,650 --> 00:09:55,570 So the ex ante allocation is set the marginal utilities 169 00:09:55,570 --> 00:10:01,280 basically equal to each other, or equal to a constant. 170 00:10:01,280 --> 00:10:04,540 This constant would be the ratio of Pareto weights. 171 00:10:04,540 --> 00:10:07,720 I'm not saying that two members have to be treated equally 172 00:10:07,720 --> 00:10:09,480 within the household. 173 00:10:09,480 --> 00:10:12,160 It could be very asymmetric. 174 00:10:12,160 --> 00:10:15,700 We usually have lambda 1 over lambda 2, or mu 1 over mu 2, 175 00:10:15,700 --> 00:10:19,990 or some ratio of those ex ante given Pareto weights. 176 00:10:19,990 --> 00:10:21,970 That's all embedded up here in the constant. 177 00:10:21,970 --> 00:10:26,740 Of course, convenient part is the indirect utility 178 00:10:26,740 --> 00:10:31,580 of household 1 is just linear, because that person had 179 00:10:31,580 --> 00:10:33,910 a utility that depended only on consumption. 180 00:10:33,910 --> 00:10:36,800 And it was linear in consumption. 181 00:10:36,800 --> 00:10:39,040 So we can now, with this constant, 182 00:10:39,040 --> 00:10:43,000 if we carry it around and multiply, you know, 183 00:10:43,000 --> 00:10:47,390 keep track that parameters get added or multiplied 184 00:10:47,390 --> 00:10:50,840 to it, that we can get a closed form solution from this 185 00:10:50,840 --> 00:10:53,090 for the transfer rule. 186 00:10:53,090 --> 00:10:55,370 And we already know what consumption and leisure 187 00:10:55,370 --> 00:10:59,690 are for person 2 as a function of the transfer. 188 00:10:59,690 --> 00:11:00,870 So we solve that. 189 00:11:00,870 --> 00:11:03,420 And I don't know, it's just algebra. 190 00:11:03,420 --> 00:11:06,120 What do you want to see down here? 191 00:11:06,120 --> 00:11:11,580 Well, person 1's consumption is moving around one to one 192 00:11:11,580 --> 00:11:14,380 with non-labor income. 193 00:11:14,380 --> 00:11:19,050 So as anticipated, member 1 is absorbing all of that risk 194 00:11:19,050 --> 00:11:22,120 and member 2 is absorbing none of it. 195 00:11:22,120 --> 00:11:32,990 But the wage is affecting consumption and more obviously 196 00:11:32,990 --> 00:11:35,620 labor supply of person 2. 197 00:11:35,620 --> 00:11:41,840 And that wage is actually affecting person 2 as well. 198 00:11:41,840 --> 00:11:43,130 Here it is down here in-- 199 00:11:43,130 --> 00:11:46,980 person 1, sorry, in terms of person 1's consumption. 200 00:11:51,240 --> 00:11:56,190 And it's doing it in a particular way basically. 201 00:11:56,190 --> 00:11:59,310 So this paper is called sharing wage risk. 202 00:11:59,310 --> 00:12:03,360 And both these members will share the wage risk, 203 00:12:03,360 --> 00:12:07,020 even though only person 2 can work more or less hours 204 00:12:07,020 --> 00:12:07,890 at that wage. 205 00:12:13,510 --> 00:12:16,480 So in some sense, leisure pooling 206 00:12:16,480 --> 00:12:26,680 is a bit different from consumption pooling in the way 207 00:12:26,680 --> 00:12:28,660 that they're going to want to adjust 208 00:12:28,660 --> 00:12:33,000 their hours is going to depend on the outside opportunities. 209 00:12:33,000 --> 00:12:33,980 So that's the summary. 210 00:12:33,980 --> 00:12:38,130 And then we'll generalize this case. 211 00:12:38,130 --> 00:12:42,950 It's not general, because person 1 was risk neutral. 212 00:12:42,950 --> 00:12:44,210 Here's the general case. 213 00:12:44,210 --> 00:12:46,410 There are S states of the world. 214 00:12:46,410 --> 00:12:49,910 There's a risk sharing group of households, as in a village 215 00:12:49,910 --> 00:12:53,260 or township or something. 216 00:12:53,260 --> 00:12:58,655 And every household H has individual members. 217 00:12:58,655 --> 00:13:00,230 It could be more than one. 218 00:13:00,230 --> 00:13:02,750 It's likely to be two or three. 219 00:13:02,750 --> 00:13:04,670 This is meant to be realistic. 220 00:13:04,670 --> 00:13:09,090 And we actually go to the data with these specifications. 221 00:13:09,090 --> 00:13:12,500 And we have hours and labor force participation 222 00:13:12,500 --> 00:13:14,780 for every member of the household. 223 00:13:14,780 --> 00:13:18,740 So we normally only have consumption for the household. 224 00:13:18,740 --> 00:13:20,550 So we kind of throw up our hands a bit, 225 00:13:20,550 --> 00:13:23,498 but here, we have labor at the level of individuals. 226 00:13:23,498 --> 00:13:25,040 And we definitely want to keep track. 227 00:13:28,250 --> 00:13:29,990 The consumption of household H is 228 00:13:29,990 --> 00:13:33,200 a sum of consumption of individual members. 229 00:13:33,200 --> 00:13:36,530 That's true in theory, even if we don't measure it 230 00:13:36,530 --> 00:13:38,930 individually in practice. 231 00:13:38,930 --> 00:13:40,700 Aggregate consumption in the village 232 00:13:40,700 --> 00:13:44,240 is a sum of consumption across the households. 233 00:13:44,240 --> 00:13:45,470 Nothing surprising there. 234 00:13:45,470 --> 00:13:48,170 Utilities of everyone stays strictly increasing 235 00:13:48,170 --> 00:13:49,385 and concave. 236 00:13:52,190 --> 00:13:58,880 And household H faces a vector of wage and non-labor income 237 00:13:58,880 --> 00:14:00,960 variation. 238 00:14:00,960 --> 00:14:06,170 You know the S is a subscript on the wages of person 239 00:14:06,170 --> 00:14:10,590 1, the wages of person 2, for how many people 240 00:14:10,590 --> 00:14:12,120 there are in this household. 241 00:14:12,120 --> 00:14:13,920 And again, here although it really 242 00:14:13,920 --> 00:14:17,302 doesn't matter because we're going to added up anyway, 243 00:14:17,302 --> 00:14:19,260 you could say different people in the household 244 00:14:19,260 --> 00:14:20,580 have different occupations. 245 00:14:20,580 --> 00:14:22,110 Some are helping on the farm. 246 00:14:22,110 --> 00:14:24,900 Other people run the business exclusively. 247 00:14:24,900 --> 00:14:28,300 You could talk about the non-wage income. 248 00:14:28,300 --> 00:14:32,460 If there's perfect markets, which we're going to assume, 249 00:14:32,460 --> 00:14:36,000 then the profits of the firm are as 250 00:14:36,000 --> 00:14:39,870 if they had supply their own labor to the market 251 00:14:39,870 --> 00:14:44,490 and hire other labor to run the business, which is problematic. 252 00:14:44,490 --> 00:14:48,680 But, you know, then you get the usual sort of separation. 253 00:14:48,680 --> 00:14:52,350 And so these are really like profit numbers. 254 00:14:57,990 --> 00:15:01,630 But this is the aggregate of overall individuals 255 00:15:01,630 --> 00:15:03,280 in the household. 256 00:15:03,280 --> 00:15:06,520 This is what we've been calling household profits. 257 00:15:06,520 --> 00:15:10,060 And finally, the resources available 258 00:15:10,060 --> 00:15:13,390 are household profits plus gifts and other things. 259 00:15:13,390 --> 00:15:16,870 These taus are not yet determined. 260 00:15:16,870 --> 00:15:22,607 They're given for this household H in state S. In a minute 261 00:15:22,607 --> 00:15:24,440 they're going to get determined endogenously 262 00:15:24,440 --> 00:15:26,355 from the rest of the village. 263 00:15:26,355 --> 00:15:27,980 So, again, we're going to kind of solve 264 00:15:27,980 --> 00:15:33,312 individual problems, household problems, village problems, 265 00:15:33,312 --> 00:15:34,395 and sort of build upwards. 266 00:15:37,820 --> 00:15:40,940 So what does the household do? 267 00:15:40,940 --> 00:15:45,620 It maximizes these new weighted sums 268 00:15:45,620 --> 00:15:52,310 of utilities of its individual members, summing over states. 269 00:15:52,310 --> 00:15:54,320 And actually, we could sum over dates. 270 00:15:54,320 --> 00:15:57,570 But you already know that doesn't matter. 271 00:15:57,570 --> 00:15:59,960 There's nothing you know particularly inter-temporal 272 00:15:59,960 --> 00:16:02,300 about this-- 273 00:16:02,300 --> 00:16:04,550 well, these sub-problems apply even when 274 00:16:04,550 --> 00:16:06,560 the household as a whole can borrow and lend 275 00:16:06,560 --> 00:16:09,210 with the outside, et cetera. 276 00:16:09,210 --> 00:16:12,740 And just simplify by getting rid of that for now. 277 00:16:12,740 --> 00:16:17,000 Common probability over states S. Utilities are allowed 278 00:16:17,000 --> 00:16:20,720 to depend on individual i. 279 00:16:20,720 --> 00:16:25,900 We're going to try to retain as much heterogeneity as possible, 280 00:16:25,900 --> 00:16:28,390 although it's sometimes problematic how much we 281 00:16:28,390 --> 00:16:30,250 can allow in the data. 282 00:16:30,250 --> 00:16:34,030 And here's the sort of collective resource constraint 283 00:16:34,030 --> 00:16:39,200 for the household H. It's the same as before. 284 00:16:39,200 --> 00:16:41,710 We're just summing over all the individual members. 285 00:16:41,710 --> 00:16:47,950 This is the sum consumption, sum of the valuation of leisure, 286 00:16:47,950 --> 00:16:52,150 equal to full income, including any taxes 287 00:16:52,150 --> 00:16:54,632 or subsidies the household is getting 288 00:16:54,632 --> 00:16:55,840 from the rest of the village. 289 00:16:58,720 --> 00:17:03,250 These Pareto weights mu are kind of taken as given. 290 00:17:03,250 --> 00:17:06,190 That's not to say there aren't forces that determine them-- 291 00:17:06,190 --> 00:17:10,089 you know, the marriage market, one person 292 00:17:10,089 --> 00:17:12,700 has a lot more income than the other, all this bargaining. 293 00:17:12,700 --> 00:17:17,660 But any bargaining that takes place here is entirely ex ante. 294 00:17:17,660 --> 00:17:24,710 And it is assumed to be fixed and unalterable subsequently 295 00:17:24,710 --> 00:17:27,869 as states of the world are realized. 296 00:17:27,869 --> 00:17:31,370 You know, we haven't talked about it in this class. 297 00:17:31,370 --> 00:17:33,590 I think you've probably seen it in other classes, 298 00:17:33,590 --> 00:17:35,960 this whole literature on the unitary household 299 00:17:35,960 --> 00:17:39,380 and, you know, ex post bargaining, 300 00:17:39,380 --> 00:17:43,160 when opportunities of the spouse increase and so on. 301 00:17:43,160 --> 00:17:44,300 They may take more goods. 302 00:17:44,300 --> 00:17:47,690 They may better dictate what household is consuming. 303 00:17:47,690 --> 00:17:49,070 That's all suppressed here. 304 00:17:49,070 --> 00:17:54,030 It's buried in these fixed Pareto weights. 305 00:17:54,030 --> 00:17:59,810 The idea is to see how far we can get even assuming that. 306 00:17:59,810 --> 00:18:04,850 OK, well, then we have the Marshallian demand. 307 00:18:04,850 --> 00:18:07,280 I only say that with emphasis because we're 308 00:18:07,280 --> 00:18:10,130 going to go Hicks and Frisch in a minute. 309 00:18:10,130 --> 00:18:14,030 But this is the regular demand for leisure 310 00:18:14,030 --> 00:18:18,450 that solves the individual's optimization problem. 311 00:18:18,450 --> 00:18:21,410 This is an individual i in household H. 312 00:18:21,410 --> 00:18:24,350 This, apart from the more cumbersome notation, 313 00:18:24,350 --> 00:18:26,870 is exactly what we went through before. 314 00:18:26,870 --> 00:18:31,370 This is some transfer that individual i is getting 315 00:18:31,370 --> 00:18:34,013 in state S from the rest-- 316 00:18:34,013 --> 00:18:35,930 giving or getting from the rest of the members 317 00:18:35,930 --> 00:18:36,680 of the household. 318 00:18:36,680 --> 00:18:39,590 This is the valuation of the time 319 00:18:39,590 --> 00:18:41,210 endowment for individual i. 320 00:18:41,210 --> 00:18:44,900 And in the left-hand side is the sum of expenditures 321 00:18:44,900 --> 00:18:48,800 on consumption and leisure. 322 00:18:48,800 --> 00:18:53,720 And that after maximization gives you the indirect utility 323 00:18:53,720 --> 00:18:57,560 function, which clearly depends on the wage 324 00:18:57,560 --> 00:18:59,780 and on this transfer. 325 00:19:10,040 --> 00:19:16,310 So for the household to have an objective function, 326 00:19:16,310 --> 00:19:22,570 we can call it sort of the Pareto mu weighted sum 327 00:19:22,570 --> 00:19:26,410 of the value functions of the individuals. 328 00:19:26,410 --> 00:19:29,050 Again, we went through this in the baby example 329 00:19:29,050 --> 00:19:30,205 at the beginning. 330 00:19:32,880 --> 00:19:35,730 And then the problem of the village-- 331 00:19:35,730 --> 00:19:38,640 note that now we summed over H-- 332 00:19:38,640 --> 00:19:45,780 is to maximize this household by household expected utility, 333 00:19:45,780 --> 00:19:49,920 and now making it expected because it's conditioned 334 00:19:49,920 --> 00:19:55,590 on state S. And here's the constraint that these transfers 335 00:19:55,590 --> 00:19:58,230 stay within the village have to add up 336 00:19:58,230 --> 00:20:01,800 to zero if the village is the risk sharing group you 337 00:20:01,800 --> 00:20:04,590 want to be considering. 338 00:20:08,510 --> 00:20:12,800 One first order condition, you know, 339 00:20:12,800 --> 00:20:15,740 basically says that the marginal utility of the household 340 00:20:15,740 --> 00:20:23,990 respective transfers in state S is just pre-multiplied 341 00:20:23,990 --> 00:20:26,900 by the probability and then this lambda HS-- 342 00:20:26,900 --> 00:20:30,740 so this lambda HS is like the shadow price 343 00:20:30,740 --> 00:20:33,520 on the budget constrain of the household at state 344 00:20:33,520 --> 00:20:38,740 S. It reflects how tight or loose 345 00:20:38,740 --> 00:20:40,600 the optimization problem is, just 346 00:20:40,600 --> 00:20:43,360 like in standard price theory. 347 00:20:43,360 --> 00:20:45,040 It's just the Lagrange multiplier 348 00:20:45,040 --> 00:20:46,780 on the budget constraint. 349 00:20:46,780 --> 00:20:49,820 It's also going to equal something else. 350 00:20:49,820 --> 00:20:55,452 But so far I haven't talked about it in the notation. 351 00:20:55,452 --> 00:20:56,910 It's going to equal something else, 352 00:20:56,910 --> 00:20:59,820 because these sum of the transfers are zero. 353 00:20:59,820 --> 00:21:03,720 So there's like a collective resource constraint that isn't 354 00:21:03,720 --> 00:21:05,250 written out here explicitly. 355 00:21:05,250 --> 00:21:08,970 And that thing is going to pick up a Lagrange multiplier. 356 00:21:08,970 --> 00:21:10,610 And that Lagrange multiplier is going 357 00:21:10,610 --> 00:21:15,630 to be common over all the households, 358 00:21:15,630 --> 00:21:19,800 just like it was for the consumption problem. 359 00:21:19,800 --> 00:21:27,160 OK, so here's an example, Cobb-Douglas coefficients 360 00:21:27,160 --> 00:21:33,350 are depending on i and H raised to a power. 361 00:21:33,350 --> 00:21:37,570 This obvious generalization of the example. 362 00:21:37,570 --> 00:21:40,990 We have a little corner to worry about here. 363 00:21:40,990 --> 00:21:45,160 You know, the way to see this is putting w over here, 364 00:21:45,160 --> 00:21:48,250 this is the expenditures on leisure. 365 00:21:48,250 --> 00:21:50,815 And expenditures on leisure ought to be equal to-- 366 00:21:54,780 --> 00:21:57,642 well, these add up to 1, basically-- 367 00:21:57,642 --> 00:22:00,400 I almost think that's a typo. 368 00:22:00,400 --> 00:22:03,490 Should be 1 minus alpha-- 369 00:22:03,490 --> 00:22:05,180 the expenditure share on leisure. 370 00:22:09,150 --> 00:22:16,140 But what happens if this amount, given this full income, 371 00:22:16,140 --> 00:22:21,480 this leisure that individual i is supposed to be consuming, 372 00:22:21,480 --> 00:22:24,450 exceeds his time endowment? 373 00:22:24,450 --> 00:22:25,825 Then you've hit a binding corner. 374 00:22:28,820 --> 00:22:34,150 So hence the min, which is this cannot exceed this. 375 00:22:34,150 --> 00:22:35,760 When it's less, it's no problem. 376 00:22:35,760 --> 00:22:40,830 You just when hours are less, you do those hours. 377 00:22:40,830 --> 00:22:43,860 When hours are more, you do the max. 378 00:22:43,860 --> 00:22:50,200 Now, let me just say this is very natural in this problem 379 00:22:50,200 --> 00:22:52,500 when the time endowment is fixed. 380 00:22:52,500 --> 00:22:57,390 But you could also imagine other indivisibilities. 381 00:22:57,390 --> 00:23:00,810 You could imagine that you could only supply 382 00:23:00,810 --> 00:23:02,280 discrete amount of hours. 383 00:23:02,280 --> 00:23:06,930 Or something like in the US, typically you 384 00:23:06,930 --> 00:23:09,660 have 8-hour days and 40-hour weeks, and that's it. 385 00:23:09,660 --> 00:23:12,150 And you can't vary your hours. 386 00:23:12,150 --> 00:23:15,210 So you can load other restrictions in here. 387 00:23:15,210 --> 00:23:20,310 And in the data, there is enormous variability 388 00:23:20,310 --> 00:23:23,230 in non-participation. 389 00:23:23,230 --> 00:23:25,510 Month by month, households will sit out 390 00:23:25,510 --> 00:23:28,660 for substantial periods of times and then re-enter 391 00:23:28,660 --> 00:23:29,540 the labor force. 392 00:23:29,540 --> 00:23:32,215 So something is making that happen. 393 00:23:36,470 --> 00:23:38,000 And actually, it's the other corner. 394 00:23:38,000 --> 00:23:42,380 It's more like zeros, not working up to the max. 395 00:23:42,380 --> 00:23:43,420 Yes? 396 00:23:43,420 --> 00:23:47,420 AUDIENCE: So it only gets a corner solution 397 00:23:47,420 --> 00:23:52,160 if that household's Pareto bases is too large for that agent? 398 00:23:52,160 --> 00:23:54,440 ROBERT TOWNSEND: That's one of the factors. 399 00:23:54,440 --> 00:23:56,450 No, too small. 400 00:23:56,450 --> 00:23:59,000 So-- oh, too large, sorry, leisure. 401 00:23:59,000 --> 00:24:01,730 And I just made a mistake, absolutely, yeah. 402 00:24:01,730 --> 00:24:05,180 So when the Pareto weight is high and leisure is valued, 403 00:24:05,180 --> 00:24:07,130 then they want to do maximum leisure. 404 00:24:07,130 --> 00:24:09,710 They set leisure equal to the time endowment and work hours 405 00:24:09,710 --> 00:24:11,030 are zero. 406 00:24:11,030 --> 00:24:16,645 So that's one thing, but it depends on the wage. 407 00:24:16,645 --> 00:24:18,020 And it's actually going to depend 408 00:24:18,020 --> 00:24:21,770 on how binding the household's resource constraint is. 409 00:24:21,770 --> 00:24:24,360 So there's two other factors. 410 00:24:24,360 --> 00:24:29,610 But you're right about the Pareto weight. 411 00:24:29,610 --> 00:24:33,800 So we can solve out for the value functions in these work 412 00:24:33,800 --> 00:24:35,390 and no work branches. 413 00:24:35,390 --> 00:24:39,280 I'm not sure that is very enlightening. 414 00:24:39,280 --> 00:24:41,840 There is going to be a critical wage, as I was just 415 00:24:41,840 --> 00:24:45,080 anticipating, where that constraint is binding 416 00:24:45,080 --> 00:24:50,480 or not if the wages are higher than this critical number, 417 00:24:50,480 --> 00:24:53,090 the individual would be working. 418 00:24:53,090 --> 00:24:55,110 And if it's lower than that critical number, 419 00:24:55,110 --> 00:24:57,290 they're not going to be working. 420 00:24:57,290 --> 00:24:58,550 So there is a threshold. 421 00:25:03,530 --> 00:25:06,020 And it turns out it's smooth as the wage-- there's 422 00:25:06,020 --> 00:25:08,630 no jumps in this problem, at least. 423 00:25:08,630 --> 00:25:10,490 You can see it in the value functions. 424 00:25:10,490 --> 00:25:14,000 You can see it in the way the wage moves. 425 00:25:14,000 --> 00:25:16,760 But again, I don't think it's worth getting 426 00:25:16,760 --> 00:25:20,870 bogged down in the algebra to make that point. 427 00:25:24,010 --> 00:25:26,820 In other words, hours will kindly smoothly 428 00:25:26,820 --> 00:25:29,610 stay at zero until the wage goes above this threshold. 429 00:25:29,610 --> 00:25:35,920 And then hours will start to pick up in a regular way. 430 00:25:35,920 --> 00:25:39,940 So here's what I just mentioned to Yeng, 431 00:25:39,940 --> 00:25:44,170 which is that households are less likely to participate when 432 00:25:44,170 --> 00:25:50,610 the wage is low, when the household is doing well, 433 00:25:50,610 --> 00:25:54,410 and when the Pareto weight is large. 434 00:25:54,410 --> 00:25:58,310 Or conversely, you'll see greater participation, 435 00:25:58,310 --> 00:26:02,400 and condition on participation, greater hours 436 00:26:02,400 --> 00:26:07,040 when the wage is high, when the household is doing badly, 437 00:26:07,040 --> 00:26:15,670 meaning that the shadow price on the budget constraint is high, 438 00:26:15,670 --> 00:26:18,160 and when this person's Pareto weight is small. 439 00:26:18,160 --> 00:26:19,630 You know, make the slaves work. 440 00:26:26,460 --> 00:26:27,480 This looks awful. 441 00:26:30,780 --> 00:26:33,330 It supposed to be a good thing that we 442 00:26:33,330 --> 00:26:37,740 are able to analytically solve. 443 00:26:37,740 --> 00:26:40,080 So let me highlight something. 444 00:26:40,080 --> 00:26:44,190 There's two equations on the slide. 445 00:26:44,190 --> 00:26:48,130 There's a reservation wage and an hour's equation. 446 00:26:48,130 --> 00:26:48,630 OK? 447 00:26:53,810 --> 00:26:55,150 Actually look down here first. 448 00:26:59,860 --> 00:27:03,450 The reservation wage for individual i in the household h 449 00:27:03,450 --> 00:27:07,440 has a constant term and something 450 00:27:07,440 --> 00:27:14,230 that depends on the shadow price of the budget. 451 00:27:14,230 --> 00:27:16,770 Now, when we did the consumption risk sharing thing, 452 00:27:16,770 --> 00:27:20,070 we talked about the shadow price of consumption. 453 00:27:20,070 --> 00:27:21,300 I'm kind of like tongue tied. 454 00:27:21,300 --> 00:27:22,920 I don't quite know what to call it. 455 00:27:22,920 --> 00:27:25,620 It's more than consumption, because we 456 00:27:25,620 --> 00:27:26,970 have leisure in this problem. 457 00:27:26,970 --> 00:27:29,050 But we did have a budget constraint. 458 00:27:29,050 --> 00:27:32,340 So it's the shadow price on the budget constraint. 459 00:27:32,340 --> 00:27:36,480 And there's no H on this guy, because this thing represents 460 00:27:36,480 --> 00:27:39,570 that all the individuals and all the households in the village 461 00:27:39,570 --> 00:27:41,920 are pooling all this risk. 462 00:27:41,920 --> 00:27:45,270 So there's like a common community level resource 463 00:27:45,270 --> 00:27:46,740 constraint. 464 00:27:46,740 --> 00:27:50,510 That's the content of the theory. 465 00:27:50,510 --> 00:27:55,580 And here's hours actually worked when working. 466 00:27:55,580 --> 00:27:57,780 And again, it has a constant term. 467 00:27:57,780 --> 00:28:03,170 It has this same shadow price object, DS, 468 00:28:03,170 --> 00:28:06,200 in it, and also on the wage. 469 00:28:06,200 --> 00:28:08,760 Now, the wage just reflects the fact that, 470 00:28:08,760 --> 00:28:11,720 as we said before, the higher the wage, 471 00:28:11,720 --> 00:28:15,110 the more you're likely to make someone work. 472 00:28:28,460 --> 00:28:32,450 And so now we can maybe get the courage to go back up 473 00:28:32,450 --> 00:28:34,910 and look at what all these objects are. 474 00:28:34,910 --> 00:28:36,710 Look at all the beautiful restrictions 475 00:28:36,710 --> 00:28:42,230 that theory is placing on these regression coefficients. 476 00:28:42,230 --> 00:28:44,750 First of all, why all the i's and h's? 477 00:28:44,750 --> 00:28:48,380 Well, we allowed a lot of heterogeneity 478 00:28:48,380 --> 00:28:51,410 in those Cobb-Douglas coefficients and the curvatures 479 00:28:51,410 --> 00:28:52,760 for each of the households. 480 00:28:58,640 --> 00:29:02,560 Let's spot some familiar-- this is all preference stuff. 481 00:29:09,990 --> 00:29:13,330 This is cool for me. 482 00:29:15,960 --> 00:29:19,830 This is the log of the probability weighted shadow 483 00:29:19,830 --> 00:29:26,190 price in the whole village. 484 00:29:26,190 --> 00:29:26,970 And what's this? 485 00:29:26,970 --> 00:29:29,020 This is the risk aversion. 486 00:29:29,020 --> 00:29:32,770 So you remember that stuff about risk tolerance? 487 00:29:32,770 --> 00:29:40,050 So, you know, the greater gamma, the less risk tolerant they 488 00:29:40,050 --> 00:29:40,740 are-- 489 00:29:40,740 --> 00:29:43,085 sorry, going the wrong way. 490 00:29:43,085 --> 00:29:46,730 This gamma is the curvature in the utility function. 491 00:29:46,730 --> 00:29:49,890 So-- oh, there's a negative sign there, right. 492 00:29:49,890 --> 00:29:53,400 So basically what it's saying is the more risk 493 00:29:53,400 --> 00:29:56,370 averse that an individual is, the less 494 00:29:56,370 --> 00:29:59,310 you should see that its hours are moving around 495 00:29:59,310 --> 00:30:00,660 with this aggregate state. 496 00:30:03,920 --> 00:30:07,780 So that's the leisure version of the consumption equations 497 00:30:07,780 --> 00:30:08,470 we had before. 498 00:30:24,980 --> 00:30:28,340 I mean here's Pareto weights in here, for example, 499 00:30:28,340 --> 00:30:31,610 in the critical wage threshold. 500 00:30:31,610 --> 00:30:33,590 This is the Pareto weight of the household. 501 00:30:33,590 --> 00:30:36,020 This is the Pareto weight of the individual. 502 00:30:36,020 --> 00:30:39,260 And the higher this thing is, the higher that wage 503 00:30:39,260 --> 00:30:41,810 is going to be, because that's basically 504 00:30:41,810 --> 00:30:44,370 the way you take your leisure. 505 00:30:44,370 --> 00:30:45,122 Yes? 506 00:30:45,122 --> 00:30:47,180 AUDIENCE: So before we were talking 507 00:30:47,180 --> 00:30:50,690 about it's great to see all these restrictions because 508 00:30:50,690 --> 00:30:53,340 of being familiar with the data and doing regression. 509 00:30:53,340 --> 00:30:57,740 But we will never have data on a Pareto weight, right? 510 00:30:57,740 --> 00:31:00,350 That's not a real thing? 511 00:31:00,350 --> 00:31:01,700 ROBERT TOWNSEND: That's true. 512 00:31:01,700 --> 00:31:02,390 But-- 513 00:31:02,390 --> 00:31:04,640 AUDIENCE: If that's correlated with other stuff that's 514 00:31:04,640 --> 00:31:06,830 going to start moving around the other betas 515 00:31:06,830 --> 00:31:09,553 that we're estimating on the stuff we can see, right? 516 00:31:09,553 --> 00:31:11,720 ROBERT TOWNSEND: Yeah, but basically-- that's right. 517 00:31:11,720 --> 00:31:13,850 And that's what this is basically. 518 00:31:13,850 --> 00:31:17,510 So you start looking at what the regression coefficients are. 519 00:31:20,770 --> 00:31:24,970 For example, here's this one thing, the risk aversion 520 00:31:24,970 --> 00:31:28,900 of individual i and household h, and there's an F on there. 521 00:31:28,900 --> 00:31:30,960 So where was the F thing? 522 00:31:30,960 --> 00:31:34,450 The F thing was what I was highlighting right here. 523 00:31:37,830 --> 00:31:39,290 So now this is a fixed effect. 524 00:31:39,290 --> 00:31:40,430 We don't see it. 525 00:31:40,430 --> 00:31:43,370 But you can put a time bearing fixed effect 526 00:31:43,370 --> 00:31:45,290 for the whole village. 527 00:31:45,290 --> 00:31:48,170 And then estimate this regression coefficient. 528 00:31:48,170 --> 00:31:51,830 And the theory is telling you that's 1 over the coefficient 529 00:31:51,830 --> 00:31:53,750 of relative risk aversion. 530 00:31:53,750 --> 00:31:58,610 And so now you can work backwards, you know-- 531 00:32:03,268 --> 00:32:04,810 AUDIENCE: Wouldn't that be correlated 532 00:32:04,810 --> 00:32:06,448 with the Pareto weight on me? 533 00:32:06,448 --> 00:32:07,750 ROBERT TOWNSEND: Mm, hmm. 534 00:32:07,750 --> 00:32:10,270 No. 535 00:32:10,270 --> 00:32:12,840 No, we didn't see that in the-- 536 00:32:12,840 --> 00:32:14,970 AUDIENCE: Oh, no, sorry, what I meant 537 00:32:14,970 --> 00:32:17,730 is if I don't have the Pareto weight-- 538 00:32:17,730 --> 00:32:19,635 so that'll be like fixed effect, right? 539 00:32:19,635 --> 00:32:21,760 ROBERT TOWNSEND: The Pareto weights is like a fix-- 540 00:32:21,760 --> 00:32:24,140 this is a time bearing fixed effect. 541 00:32:24,140 --> 00:32:26,070 And the Pareto weights are going to show up-- 542 00:32:30,705 --> 00:32:31,330 where are they? 543 00:32:31,330 --> 00:32:32,860 Over here. 544 00:32:32,860 --> 00:32:34,142 Here's one. 545 00:32:34,142 --> 00:32:35,350 AUDIENCE: Can you have some-- 546 00:32:35,350 --> 00:32:37,642 ROBERT TOWNSEND: This is the households' Pareto weight. 547 00:32:37,642 --> 00:32:39,790 This is the individual's Pareto weight. 548 00:32:39,790 --> 00:32:42,850 Granted there's a little bit of these alphas to worry about. 549 00:32:42,850 --> 00:32:44,540 So we'll have to grab them. 550 00:32:44,540 --> 00:32:47,170 But part of this fixed effect, this 551 00:32:47,170 --> 00:32:51,990 is not varying with time or states or anything else. 552 00:32:51,990 --> 00:32:54,240 AUDIENCE: So you can have like an individual effect is 553 00:32:54,240 --> 00:32:55,370 what you're saying. 554 00:32:55,370 --> 00:32:56,287 ROBERT TOWNSEND: Yeah. 555 00:33:00,490 --> 00:33:02,500 So that's sort of-- the algebra is 556 00:33:02,500 --> 00:33:05,290 if you had all these regression coefficients and so on, 557 00:33:05,290 --> 00:33:13,450 then you basically can identify almost all these parameters. 558 00:33:13,450 --> 00:33:15,780 The thing that you can actually get 559 00:33:15,780 --> 00:33:21,050 is the absolute value of the risk tolerance. 560 00:33:21,050 --> 00:33:22,840 And we actually saw that earlier. 561 00:33:22,840 --> 00:33:25,440 It's the ratio of the risk tolerance of household i 562 00:33:25,440 --> 00:33:28,560 relative to other members that you're actually 563 00:33:28,560 --> 00:33:30,270 able to identify. 564 00:33:30,270 --> 00:33:34,300 You can see who's more risk averse than others, but not-- 565 00:33:34,300 --> 00:33:39,360 OK, and actually the paper itself goes through-- 566 00:33:39,360 --> 00:33:40,090 it's long. 567 00:33:40,090 --> 00:33:42,060 I'm afraid it's quite tedious-- 568 00:33:42,060 --> 00:33:44,160 goes through, you know, this parametric example. 569 00:33:44,160 --> 00:33:46,650 It actually goes through non-parametric stuff. 570 00:33:46,650 --> 00:33:50,310 Pierre-Andre has figured out with his co-authors 571 00:33:50,310 --> 00:33:53,760 how to identify tons of stuff, just based on labor supply, 572 00:33:53,760 --> 00:33:57,060 even though there's all this underlying consumption 573 00:33:57,060 --> 00:33:58,820 stuff going on. 574 00:33:58,820 --> 00:34:02,560 You use data from Britain. 575 00:34:02,560 --> 00:34:05,010 OK. 576 00:34:05,010 --> 00:34:06,491 So yep? 577 00:34:06,491 --> 00:34:08,699 AUDIENCE: So you starting out with the multiplication 578 00:34:08,699 --> 00:34:13,309 that consumption will have to equal to waste. 579 00:34:13,309 --> 00:34:14,790 ROBERT TOWNSEND: Yeah. 580 00:34:14,790 --> 00:34:18,643 AUDIENCE: But your paper in 1994-- 581 00:34:18,643 --> 00:34:19,560 ROBERT TOWNSEND: Yeah. 582 00:34:19,560 --> 00:34:21,822 AUDIENCE: So how do you reconcile with this? 583 00:34:25,190 --> 00:34:28,090 ROBERT TOWNSEND: Well, I mean, the first answer was, you know, 584 00:34:28,090 --> 00:34:30,889 I assumed the problem away. 585 00:34:30,889 --> 00:34:31,909 Actually, not quite. 586 00:34:31,909 --> 00:34:35,989 If you look, you'll see that I had put measures of hours 587 00:34:35,989 --> 00:34:38,840 in the consumption equations. 588 00:34:38,840 --> 00:34:41,150 I was aware of this even then. 589 00:34:44,750 --> 00:34:47,820 But it certainly would be easy to make a mistake. 590 00:34:47,820 --> 00:34:52,260 And people are often critical, like puzzled, how can you 591 00:34:52,260 --> 00:34:54,940 say income shouldn't matter? 592 00:34:54,940 --> 00:34:56,880 And here, we are distinguishing the income 593 00:34:56,880 --> 00:34:59,520 that's coming from labor supply versus the income that's 594 00:34:59,520 --> 00:35:01,230 non-labor. 595 00:35:01,230 --> 00:35:02,460 And it matters. 596 00:35:02,460 --> 00:35:05,450 The theory places restrictions on how. 597 00:35:05,450 --> 00:35:08,650 So in some sense, consumption does move with income. 598 00:35:08,650 --> 00:35:12,150 If the wage is moving income, then it's moving consumption. 599 00:35:12,150 --> 00:35:14,874 And it's moving consumption of everyone. 600 00:35:14,874 --> 00:35:17,580 AUDIENCE: Not quite generally. 601 00:35:17,580 --> 00:35:20,370 ROBERT TOWNSEND: No, it's just from the first order conditions 602 00:35:20,370 --> 00:35:23,550 of the optimum problem, the baby example 603 00:35:23,550 --> 00:35:25,433 that I gave at the very beginning. 604 00:35:31,110 --> 00:35:35,150 AUDIENCE: So why are we testing a social planning 605 00:35:35,150 --> 00:35:37,750 problem instead of competitive equilibrium. 606 00:35:37,750 --> 00:35:41,365 Is that because Thailand economy is centrally-- 607 00:35:41,365 --> 00:35:43,240 ROBERT TOWNSEND: There is no social planning. 608 00:35:43,240 --> 00:35:46,030 AUDIENCE: Isn't just to see how close we get to the benchmark? 609 00:35:46,030 --> 00:35:47,800 ROBERT TOWNSEND: Yeah. 610 00:35:47,800 --> 00:35:50,080 First of all, it's not a particular benchmark, 611 00:35:50,080 --> 00:35:53,680 because those fixed effects-- 612 00:35:53,680 --> 00:35:59,264 we want to see where we are in the whole frontier, right? 613 00:35:59,264 --> 00:36:01,295 AUDIENCE: I guess there's a menu of benchmarks. 614 00:36:01,295 --> 00:36:02,170 ROBERT TOWNSEND: Yes. 615 00:36:02,170 --> 00:36:05,680 So the idea is somehow like sort of a closed thing, 616 00:36:05,680 --> 00:36:10,180 that you wouldn't leave, quote, "surplus on the table." 617 00:36:10,180 --> 00:36:13,450 That there must be markets or institutions 618 00:36:13,450 --> 00:36:18,010 or other arrangements that lead them toward efficient outcomes. 619 00:36:18,010 --> 00:36:20,560 But, yeah, it's not like-- 620 00:36:20,560 --> 00:36:23,520 it's interesting that you're against the social planner. 621 00:36:23,520 --> 00:36:31,390 It's-- and I often slip, and you caught me the other day, 622 00:36:31,390 --> 00:36:33,910 saying, you know, social planner this and that when I did 623 00:36:33,910 --> 00:36:37,060 the capital asset model. 624 00:36:37,060 --> 00:36:39,250 That's just a metaphor for-- 625 00:36:39,250 --> 00:36:41,440 it's as if the community as a whole 626 00:36:41,440 --> 00:36:46,380 is allocating resources so as to not lose any surplus. 627 00:36:46,380 --> 00:36:49,720 Now, you know, exactly what the institution-- 628 00:36:49,720 --> 00:36:51,630 so I should tell you about what we find. 629 00:36:51,630 --> 00:36:53,550 First of all, in these villages, there's 630 00:36:53,550 --> 00:36:57,090 something called labor exchange arrangements. 631 00:36:57,090 --> 00:36:59,640 And it's partly with the rice thing. 632 00:36:59,640 --> 00:37:03,240 You know, the low land gets flooded early. 633 00:37:03,240 --> 00:37:08,310 They all go down and help that guy farm his land. 634 00:37:08,310 --> 00:37:13,450 And then as the water rises, they flood the other plots. 635 00:37:13,450 --> 00:37:16,420 But they don't charge each other for the labor. 636 00:37:16,420 --> 00:37:20,120 It looks like free labor exchange. 637 00:37:20,120 --> 00:37:23,410 And it doesn't necessarily balance out either. 638 00:37:23,410 --> 00:37:26,530 Now, I'm not saying in any given economy you'd be lucky enough 639 00:37:26,530 --> 00:37:28,820 to observe something like that. 640 00:37:28,820 --> 00:37:31,120 But in these villages you actually do 641 00:37:31,120 --> 00:37:36,370 have a real institutional counterpart that might explain 642 00:37:36,370 --> 00:37:38,710 how they managed to do so well. 643 00:37:38,710 --> 00:37:39,290 Yes? 644 00:37:39,290 --> 00:37:41,665 AUDIENCE: So I'm not sure it would matter for this model. 645 00:37:41,665 --> 00:37:43,410 But the story you told is that there's 646 00:37:43,410 --> 00:37:45,160 several risk sharing arrangements 647 00:37:45,160 --> 00:37:46,250 for a different domain. 648 00:37:46,250 --> 00:37:48,490 That one was labor opportunities. 649 00:37:48,490 --> 00:37:51,500 Maybe there's a separate one for consumption. 650 00:37:51,500 --> 00:37:54,100 Would it matter-- from what perspective would it 651 00:37:54,100 --> 00:37:56,250 matter if there were one unified arrangement? 652 00:37:56,250 --> 00:37:58,130 ROBERT TOWNSEND: No, it wouldn't matter. 653 00:37:58,130 --> 00:38:01,480 But, you know, it's nice to be able to say something 654 00:38:01,480 --> 00:38:03,610 about what the mechanism is. 655 00:38:03,610 --> 00:38:06,310 You know, for some people just looking at outcomes 656 00:38:06,310 --> 00:38:08,480 isn't totally convincing. 657 00:38:08,480 --> 00:38:09,940 I must say when I started this, I 658 00:38:09,940 --> 00:38:13,480 thought it was a virtue to say we don't care how it's 659 00:38:13,480 --> 00:38:18,100 done, I'm not going to look separately as savings accounts, 660 00:38:18,100 --> 00:38:22,150 selling bullocks, borrowing, running down your grain stores, 661 00:38:22,150 --> 00:38:24,700 let's just look at the total. 662 00:38:24,700 --> 00:38:30,140 But still people want to know how it could possibly happen. 663 00:38:30,140 --> 00:38:31,970 So what's going on in these data? 664 00:38:31,970 --> 00:38:35,590 Well, I spare you all the details. 665 00:38:35,590 --> 00:38:42,510 But we put non-labor income on the right-hand side 666 00:38:42,510 --> 00:38:46,890 of the participation equations and the labor supply equations. 667 00:38:46,890 --> 00:38:53,290 And the coefficient on it is small and quite negligible. 668 00:38:53,290 --> 00:38:55,080 I mean, it's not zero. 669 00:38:55,080 --> 00:38:56,910 So we reject. 670 00:38:56,910 --> 00:38:59,730 But, you know, if you come at this-- 671 00:38:59,730 --> 00:39:02,700 and we'll see this in Seema's paper-- 672 00:39:02,700 --> 00:39:06,870 if you come at this from the traditional point of view 673 00:39:06,870 --> 00:39:10,920 in development, it would be like labor supply is your safety 674 00:39:10,920 --> 00:39:12,450 net. 675 00:39:12,450 --> 00:39:16,270 If you're getting your income is really low from crops, 676 00:39:16,270 --> 00:39:19,580 then migrate out, work for wages. 677 00:39:19,580 --> 00:39:21,510 And this says, well, not so fast. 678 00:39:21,510 --> 00:39:25,860 It might be done at a community level. 679 00:39:25,860 --> 00:39:29,010 And the test of it would be whether how well you're 680 00:39:29,010 --> 00:39:32,580 doing on your own land has any influence on your participation 681 00:39:32,580 --> 00:39:33,540 and your labor supply. 682 00:39:33,540 --> 00:39:34,980 If they're pooling risk like this, 683 00:39:34,980 --> 00:39:38,430 it shouldn't once you control for, say, village level 684 00:39:38,430 --> 00:39:40,250 fixed effects. 685 00:39:40,250 --> 00:39:42,110 And, in fact, you reject. 686 00:39:42,110 --> 00:39:46,710 But the coefficients are tiny. 687 00:39:46,710 --> 00:39:50,960 They really are sharing a lot of this risk, not all of it, 688 00:39:50,960 --> 00:39:52,030 but a lot of it. 689 00:39:55,530 --> 00:40:00,790 OK, one last thing just to tie some of this literature 690 00:40:00,790 --> 00:40:03,420 to-- oh, god. 691 00:40:03,420 --> 00:40:09,810 So this thing, this is like a famous parameter, 692 00:40:09,810 --> 00:40:12,500 because it's called the Frisch elasticity. 693 00:40:12,500 --> 00:40:19,500 And that brings to the next part of this lecture, which 694 00:40:19,500 --> 00:40:24,930 is this tension between the small estimates, micro level 695 00:40:24,930 --> 00:40:30,690 estimates, of labor elasticities compared to what we seem 696 00:40:30,690 --> 00:40:36,840 to need in a model to get aggregate hours 697 00:40:36,840 --> 00:40:40,890 and participation and move around so much. 698 00:40:40,890 --> 00:40:45,895 Now, this literature spans micro and macro and development. 699 00:40:48,570 --> 00:40:57,540 From the macro side, Chetty reviewed all of it. 700 00:40:57,540 --> 00:41:00,400 But, you know, Sargent, for example, 701 00:41:00,400 --> 00:41:05,320 but way back to Rogerson and Hansen talk about a way 702 00:41:05,320 --> 00:41:09,020 I'm going to show you an indivisibility that 703 00:41:09,020 --> 00:41:14,270 makes the overall aggregate elasticities a lot 704 00:41:14,270 --> 00:41:19,190 higher than you would get if you looked at those individuals 705 00:41:19,190 --> 00:41:19,990 in the data. 706 00:41:19,990 --> 00:41:22,190 So again, just to anticipate, this 707 00:41:22,190 --> 00:41:26,040 is a bit like zooming out and zooming in. 708 00:41:26,040 --> 00:41:27,440 You zoom in to the individuals. 709 00:41:27,440 --> 00:41:29,120 If you have labor supply and so on, 710 00:41:29,120 --> 00:41:32,270 you can estimate their micro level elasticities. 711 00:41:32,270 --> 00:41:34,430 And there's just tons of literature, 712 00:41:34,430 --> 00:41:36,530 which I suppressed from the slides, 713 00:41:36,530 --> 00:41:40,220 because it will overwhelm you of the interest 714 00:41:40,220 --> 00:41:42,770 in estimating those elasticities. 715 00:41:42,770 --> 00:41:44,990 But you could say all these individuals reside 716 00:41:44,990 --> 00:41:46,910 in a village or district. 717 00:41:46,910 --> 00:41:50,240 Let's look at what happens when there's a rainfall shock. 718 00:41:50,240 --> 00:41:52,580 Let's look at aggregate-- 719 00:41:52,580 --> 00:41:56,120 how much the wage is moving as a function of the rainfall 720 00:41:56,120 --> 00:41:59,750 shock and try to estimate from there 721 00:41:59,750 --> 00:42:03,260 how inelastic labor supply is. 722 00:42:03,260 --> 00:42:05,720 And it's natural that aggregate up over individuals 723 00:42:05,720 --> 00:42:08,060 to get an aggregate labor supply if you're 724 00:42:08,060 --> 00:42:14,000 talking about how district wages move around with rainfall. 725 00:42:14,000 --> 00:42:15,930 Well, that's Seema's paper at the end. 726 00:42:15,930 --> 00:42:20,230 She's seemingly not aware, and she didn't make a mistake. 727 00:42:20,230 --> 00:42:23,680 But it would be quite easy to make a mistake if you were 728 00:42:23,680 --> 00:42:28,160 quantitatively trying to reconcile the data that you 729 00:42:28,160 --> 00:42:31,400 use in the aggregate with the micro level elasticities. 730 00:42:31,400 --> 00:42:34,310 And so that's, as it turns out, been 731 00:42:34,310 --> 00:42:41,510 the focus of this of this macro literature, so 732 00:42:41,510 --> 00:42:42,770 many elasticities. 733 00:42:45,467 --> 00:42:47,300 And partly because the different literatures 734 00:42:47,300 --> 00:42:49,270 developed different jargon. 735 00:42:49,270 --> 00:42:53,320 There is the Hisksian elasticities 736 00:42:53,320 --> 00:42:56,350 and the Frisch elasticities. 737 00:42:56,350 --> 00:43:01,210 A Hisksian elasticity is basically compensated. 738 00:43:01,210 --> 00:43:03,490 So when you have a wage change, you 739 00:43:03,490 --> 00:43:04,840 don't just look at total hours. 740 00:43:04,840 --> 00:43:08,320 You push people back to the original indifference curve 741 00:43:08,320 --> 00:43:10,480 and slide along it. 742 00:43:10,480 --> 00:43:12,910 That's Hicks. 743 00:43:12,910 --> 00:43:16,510 Frisch has to do with variation that you 744 00:43:16,510 --> 00:43:19,330 would see if you held the marginal utility of wealth 745 00:43:19,330 --> 00:43:22,000 constant. 746 00:43:22,000 --> 00:43:23,920 Why does that come up for us? 747 00:43:23,920 --> 00:43:25,690 Oh, risk sharing. 748 00:43:25,690 --> 00:43:28,960 The marginal utility of wealth is basically 749 00:43:28,960 --> 00:43:32,980 at each date and state constant over all the individuals. 750 00:43:32,980 --> 00:43:37,300 It's a very natural object and related to the risk sharing 751 00:43:37,300 --> 00:43:38,560 literature. 752 00:43:38,560 --> 00:43:41,410 And then macro, they call-- 753 00:43:41,410 --> 00:43:43,450 just to add Frisch elasticity. 754 00:43:43,450 --> 00:43:46,390 But it's of aggregate hours. 755 00:43:46,390 --> 00:43:49,660 And every one of these things has extensive and intensive. 756 00:43:49,660 --> 00:43:53,800 And that's because there's a big variation in participation, 757 00:43:53,800 --> 00:43:58,060 not just hours in any data that people have looked at. 758 00:43:58,060 --> 00:44:00,370 I'm not sure Chetty did this. 759 00:44:00,370 --> 00:44:02,800 I'm not so sure how helpful it is. 760 00:44:05,510 --> 00:44:11,450 But the idea is the Hicks effect is like shifting a wage. 761 00:44:11,450 --> 00:44:14,420 And you're going to shift it-- 762 00:44:14,420 --> 00:44:15,890 if you're going to distinguish age, 763 00:44:15,890 --> 00:44:19,220 you shift it over the entire age profile. 764 00:44:19,220 --> 00:44:21,410 That's the way he thinks about it. 765 00:44:21,410 --> 00:44:23,660 Whereas he thinks about the Frisch elasticity 766 00:44:23,660 --> 00:44:25,835 as just one little instant. 767 00:44:28,670 --> 00:44:31,280 I have trouble relating, but anyway this is-- 768 00:44:35,240 --> 00:44:37,570 and then there's this table. 769 00:44:37,570 --> 00:44:50,460 These are micro estimates of the intensive means conditioned 770 00:44:50,460 --> 00:44:54,180 on working, how much your hours are varying with your wage. 771 00:44:54,180 --> 00:44:56,790 These are, quote unquote, "relatively low" numbers, 772 00:44:56,790 --> 00:45:01,840 0.3, 0.5. 773 00:45:01,840 --> 00:45:08,040 The extensive margin is in the micro data also not big, 0.1, 774 00:45:08,040 --> 00:45:12,980 0.2. 775 00:45:12,980 --> 00:45:17,960 What this literature is about is aggregate hours. 776 00:45:17,960 --> 00:45:22,220 Aggregate hours have higher elasticities 777 00:45:22,220 --> 00:45:23,590 than any of those numbers. 778 00:45:23,590 --> 00:45:29,570 And in particular this thing, this macro level, 779 00:45:29,570 --> 00:45:31,325 Frisch elasticity is huge. 780 00:45:36,850 --> 00:45:44,440 So in order to generate this number that we see in the data, 781 00:45:44,440 --> 00:45:47,620 and keep the micro parameters that you're 782 00:45:47,620 --> 00:45:51,630 going to fit in, to be consistent with that you have 783 00:45:51,630 --> 00:45:57,630 to generate a huge elasticity on the extensive margin somehow. 784 00:46:00,330 --> 00:46:05,255 So this is about trying to reconcile micro with macro. 785 00:46:05,255 --> 00:46:07,710 AUDIENCE: Is that bottom line, they're 786 00:46:07,710 --> 00:46:09,940 not estimates from the data? 787 00:46:09,940 --> 00:46:11,410 ROBERT TOWNSEND: Which one? 788 00:46:11,410 --> 00:46:12,532 AUDIENCE: The bottom line. 789 00:46:12,532 --> 00:46:13,990 ROBERT TOWNSEND: Yeah, they're not. 790 00:46:13,990 --> 00:46:17,000 Although this is like that. 791 00:46:17,000 --> 00:46:19,890 So let's respect the data on that dimension. 792 00:46:19,890 --> 00:46:23,230 And somehow create a very big number here somehow-- 793 00:46:23,230 --> 00:46:25,360 and I'll tell you how in a minute-- 794 00:46:25,360 --> 00:46:28,000 in order to get what we see in the data over here. 795 00:46:31,120 --> 00:46:32,900 Now, in the original slides-- 796 00:46:32,900 --> 00:46:34,220 I'll give them to you-- 797 00:46:34,220 --> 00:46:36,310 there's like six slides that now come 798 00:46:36,310 --> 00:46:39,860 you know with all these other who did this and which author 799 00:46:39,860 --> 00:46:40,430 and so on. 800 00:46:40,430 --> 00:46:45,440 And I just felt that was going to be bewildering and certainly 801 00:46:45,440 --> 00:46:46,310 time consuming. 802 00:46:46,310 --> 00:46:47,220 So I'm skipping it. 803 00:46:50,050 --> 00:46:52,930 But here's what I already went through. 804 00:46:59,670 --> 00:47:01,140 And I guess I said this too. 805 00:47:10,390 --> 00:47:13,030 So the punch line is going to be if we 806 00:47:13,030 --> 00:47:17,680 have a non-convexity in participation, 807 00:47:17,680 --> 00:47:20,170 like you either have to work full-time or not at all, 808 00:47:20,170 --> 00:47:20,800 is an extreme. 809 00:47:23,830 --> 00:47:27,190 And then we go through the mechanics of how people 810 00:47:27,190 --> 00:47:29,260 would behave in that economy. 811 00:47:29,260 --> 00:47:33,580 We can generate a sort of pseudo representative consumer. 812 00:47:33,580 --> 00:47:35,830 So that it looks as if the aggregate are 813 00:47:35,830 --> 00:47:41,543 generated as a solution to that representative household. 814 00:47:41,543 --> 00:47:43,460 And the trick is that representative household 815 00:47:43,460 --> 00:47:47,830 is going to end up with a Frisch elasticity 816 00:47:47,830 --> 00:47:54,100 in the pseudo function, which will allow huge variability 817 00:47:54,100 --> 00:47:55,555 in aggregate hours. 818 00:47:55,555 --> 00:47:58,016 It responds to wages. 819 00:47:58,016 --> 00:47:59,690 Yep. 820 00:47:59,690 --> 00:48:05,810 AUDIENCE: This doesn't match the extensive margin micro data. 821 00:48:05,810 --> 00:48:07,809 ROBERT TOWNSEND: Because it doesn't have to. 822 00:48:07,809 --> 00:48:08,392 AUDIENCE: Why? 823 00:48:11,287 --> 00:48:13,620 ROBERT TOWNSEND: Because you can populate the underlying 824 00:48:13,620 --> 00:48:18,180 individuals with actual observed micro estimates and then say 825 00:48:18,180 --> 00:48:21,360 there is this inelasticity. 826 00:48:21,360 --> 00:48:23,370 I'll show you. 827 00:48:23,370 --> 00:48:23,970 I'll show you. 828 00:48:23,970 --> 00:48:31,060 OK, so we have labor, capital, and output. 829 00:48:31,060 --> 00:48:34,160 Let's just do a single period. 830 00:48:34,160 --> 00:48:36,650 Imagine for a minute it's not stochastic either. 831 00:48:36,650 --> 00:48:42,150 We have an aggregate production function, 832 00:48:42,150 --> 00:48:48,737 as a function of aggregate capital and aggregate hours 833 00:48:48,737 --> 00:48:49,570 Why are we doing it? 834 00:48:49,570 --> 00:48:52,600 This is basically just going to allow 835 00:48:52,600 --> 00:48:55,210 us to close the model instead of having 836 00:48:55,210 --> 00:48:56,720 it open partial equilibrium. 837 00:48:56,720 --> 00:48:59,050 So we're going to get the wage and interest rate off 838 00:48:59,050 --> 00:49:00,800 of this thing. 839 00:49:00,800 --> 00:49:03,990 It's convenient. 840 00:49:03,990 --> 00:49:10,750 There are a continuum of individuals indexed by i. 841 00:49:10,750 --> 00:49:14,125 Each individual has one unit of time, one unit of capital. 842 00:49:18,040 --> 00:49:19,277 Time is indivisible. 843 00:49:19,277 --> 00:49:21,610 And you got to choose, you're either going to do leisure 844 00:49:21,610 --> 00:49:23,300 or you're going to do work. 845 00:49:23,300 --> 00:49:27,358 So that's an extreme version of the indivisibility. 846 00:49:30,350 --> 00:49:33,560 They care about consumption and leisure, 847 00:49:33,560 --> 00:49:35,200 or the disutility of work. 848 00:49:38,420 --> 00:49:43,380 But this work level is either 0 or 1 by assumption. 849 00:49:43,380 --> 00:49:47,350 So let's just normalize and say v of 0 is 0. 850 00:49:47,350 --> 00:49:49,800 But v of 1 is whatever it is. 851 00:49:49,800 --> 00:49:50,600 Let's call it m. 852 00:49:50,600 --> 00:49:52,740 It's just a real number, because you're never 853 00:49:52,740 --> 00:49:54,240 going to see at the individual level 854 00:49:54,240 --> 00:49:57,920 any other levels of hours. 855 00:49:57,920 --> 00:50:02,320 So remember m is the disutility of working 1-- 856 00:50:02,320 --> 00:50:03,850 putting all your time into work. 857 00:50:06,410 --> 00:50:09,560 What's the consumption set in this economy? 858 00:50:09,560 --> 00:50:12,740 Consumption is non-negative. 859 00:50:12,740 --> 00:50:16,220 You can't supply more capital than what you own. 860 00:50:16,220 --> 00:50:23,060 But you have this non-convexity in the labor decision. 861 00:50:23,060 --> 00:50:23,810 It's 0, 1. 862 00:50:23,810 --> 00:50:25,580 This is not an interval 0 to 1. 863 00:50:25,580 --> 00:50:27,000 It's either 0 or 1. 864 00:50:27,000 --> 00:50:29,655 It's the set consisting of just the two objects. 865 00:50:33,170 --> 00:50:36,920 So it's a non-convex consumption set. 866 00:50:36,920 --> 00:50:40,895 Linear combinations of 0 and 1 are not allowed. 867 00:50:47,410 --> 00:50:53,520 OK, so what would be a competitive equilibrium? 868 00:50:53,520 --> 00:50:57,720 Households max, firms max, markets clear. 869 00:50:57,720 --> 00:51:00,240 Here's the household max problem. 870 00:51:00,240 --> 00:51:05,010 For any individual i, solve for the consumption decision 871 00:51:05,010 --> 00:51:09,300 about participation and the capital respecting the budget 872 00:51:09,300 --> 00:51:09,870 constraint. 873 00:51:09,870 --> 00:51:13,600 Namely, you can work or not-- 874 00:51:13,600 --> 00:51:17,610 so this is either 0 or something positive-- at a given wage. 875 00:51:17,610 --> 00:51:21,810 And then you get the rental rate on your capital stock. 876 00:51:21,810 --> 00:51:25,190 And that's that. 877 00:51:25,190 --> 00:51:30,020 Firms maximize profits, paying factors of production. 878 00:51:30,020 --> 00:51:32,030 Clearly for a given f, this is going 879 00:51:32,030 --> 00:51:35,970 to generate marginal products of capital and labor 880 00:51:35,970 --> 00:51:37,050 in the whole economy. 881 00:51:45,330 --> 00:51:52,190 And if we just solve the problem this way, 882 00:51:52,190 --> 00:51:53,540 we could get an equilibrium. 883 00:51:57,940 --> 00:51:59,560 But it might not be optimal. 884 00:52:02,100 --> 00:52:07,420 We can make people better off by sort of randomizing 885 00:52:07,420 --> 00:52:09,830 who gets to work. 886 00:52:09,830 --> 00:52:13,120 How are we going to do that? 887 00:52:13,120 --> 00:52:17,960 We're going to basically create this probability object phi. 888 00:52:17,960 --> 00:52:24,780 So here would be the expected utility given a phi. 889 00:52:24,780 --> 00:52:27,470 The realization with probability phi, 890 00:52:27,470 --> 00:52:30,190 you're going to be the worker in this economy. 891 00:52:30,190 --> 00:52:34,700 With probability 1 minus phi, you're just not going to work. 892 00:52:34,700 --> 00:52:38,930 And at the moment, you can get different consumption 893 00:52:38,930 --> 00:52:40,780 for the two different branches. 894 00:52:40,780 --> 00:52:41,280 Yep? 895 00:52:43,862 --> 00:52:45,320 AUDIENCE: I sort of understand this 896 00:52:45,320 --> 00:52:48,785 is getting at which the market might be flexible. 897 00:52:48,785 --> 00:52:49,910 There's not much part-time. 898 00:52:49,910 --> 00:52:51,620 There's not much intensive margin. 899 00:52:51,620 --> 00:52:54,800 So people turn to things like household and they specialize. 900 00:52:54,800 --> 00:52:59,020 But how do you interpret the lottery as-- 901 00:52:59,020 --> 00:53:03,060 like we imposed lumpiness of working. 902 00:53:03,060 --> 00:53:05,090 And then we use the lottery to break it. 903 00:53:05,090 --> 00:53:10,930 Why not have some other way of having other types of labor 904 00:53:10,930 --> 00:53:11,430 worked? 905 00:53:14,394 --> 00:53:24,200 ROBERT TOWNSEND: Um-- well, I'm about to show you 906 00:53:24,200 --> 00:53:29,390 on the next slide the decision problem for an insurance 907 00:53:29,390 --> 00:53:30,700 company. 908 00:53:30,700 --> 00:53:33,720 And the insurance companies like pooling over 909 00:53:33,720 --> 00:53:35,630 all the individuals. 910 00:53:35,630 --> 00:53:38,570 And it's going to maximize, and there's going to be free entry. 911 00:53:38,570 --> 00:53:40,970 And that's going to drive the prices of certain things 912 00:53:40,970 --> 00:53:43,790 to be equal to their actuarial values. 913 00:53:43,790 --> 00:53:49,920 So it's as if people were buying and selling insurance. 914 00:53:49,920 --> 00:53:51,825 And they get to choose-- 915 00:53:56,330 --> 00:54:00,620 they're not forced as if by a planner 916 00:54:00,620 --> 00:54:04,550 to work or not work depending on how the roulette wheel turns. 917 00:54:04,550 --> 00:54:08,470 They actually get to choose voluntarily 918 00:54:08,470 --> 00:54:14,450 whether to decide to work full time, decide to work zero 919 00:54:14,450 --> 00:54:15,890 or be on call. 920 00:54:15,890 --> 00:54:18,470 They'd be on call, they're going to get a wage that's 921 00:54:18,470 --> 00:54:21,410 proportional to the probability, because that's 922 00:54:21,410 --> 00:54:23,248 the pooling aspect of it. 923 00:54:23,248 --> 00:54:24,960 AUDIENCE: Like [INAUDIBLE] 924 00:54:24,960 --> 00:54:26,830 ROBERT TOWNSEND: Yeah, so far. 925 00:54:26,830 --> 00:54:27,330 Yeah. 926 00:54:27,330 --> 00:54:30,470 AUDIENCE: I don't know that the lottery is so great, because it 927 00:54:30,470 --> 00:54:35,240 could be we have like some of us turn up for the job interviews, 928 00:54:35,240 --> 00:54:38,513 and the people doing the job interviews like just-- 929 00:54:38,513 --> 00:54:40,430 you know, they're picking based on some stuff. 930 00:54:40,430 --> 00:54:42,200 Maybe it's just as good as random, right? 931 00:54:42,200 --> 00:54:43,972 Like so-- 932 00:54:43,972 --> 00:54:44,930 AUDIENCE: That's crazy. 933 00:54:44,930 --> 00:54:45,888 AUDIENCE: No, it's not. 934 00:54:48,830 --> 00:54:51,055 ROBERT TOWNSEND: Disconcerting maybe. 935 00:54:51,055 --> 00:54:54,440 AUDIENCE: Suppose there are like 100 unskilled manual laborers 936 00:54:54,440 --> 00:54:56,930 turned up for a job that requires 30 laborers. 937 00:54:56,930 --> 00:54:59,520 I cannot observe past project of these laborers. 938 00:54:59,520 --> 00:55:01,360 Like I can maybe observe cleanliness 939 00:55:01,360 --> 00:55:02,810 and they're ability to speak. 940 00:55:02,810 --> 00:55:04,133 Like that's about it. 941 00:55:04,133 --> 00:55:05,300 So what am I supposed to do. 942 00:55:05,300 --> 00:55:06,675 ROBERT TOWNSEND: So that would be 943 00:55:06,675 --> 00:55:09,590 an institutional arrangement, where the markets seem 944 00:55:09,590 --> 00:55:13,820 not to clear, because not everyone gets the allocation, 945 00:55:13,820 --> 00:55:16,150 not everyone supplies labor. 946 00:55:16,150 --> 00:55:18,560 You know, they're lined up on the street corner, 947 00:55:18,560 --> 00:55:21,200 and the truck comes by, and there are only so many jobs. 948 00:55:21,200 --> 00:55:22,950 AUDIENCE: But what if we were indifferent, 949 00:55:22,950 --> 00:55:24,005 then it would still be-- 950 00:55:24,005 --> 00:55:26,130 ROBERT TOWNSEND: But there are other ways to do it. 951 00:55:26,130 --> 00:55:31,540 I mean you could have sunspot. 952 00:55:31,540 --> 00:55:35,020 You can even index off of observable things 953 00:55:35,020 --> 00:55:37,990 like rainfall. 954 00:55:37,990 --> 00:55:39,970 And then it would look like a state contingent 955 00:55:39,970 --> 00:55:45,998 contract, where the labor supply is a function of the rainfall. 956 00:55:45,998 --> 00:55:48,040 But that doesn't mean everyone's supplying labor. 957 00:55:48,040 --> 00:55:49,180 They have some arrangement. 958 00:55:49,180 --> 00:55:50,350 If it's sunny, I'm working. 959 00:55:50,350 --> 00:55:53,220 If it's raining, you're working. 960 00:55:53,220 --> 00:55:56,080 And it would be very hard to say, 961 00:55:56,080 --> 00:55:58,480 unless you were very clear headed, 962 00:55:58,480 --> 00:56:02,410 whether it's this sort of extraneous risk 963 00:56:02,410 --> 00:56:04,990 or some intrinsic risk, some underlying state 964 00:56:04,990 --> 00:56:08,500 that they were trying to insure against. 965 00:56:08,500 --> 00:56:11,355 This last interpretation is Arrow's interpretation 966 00:56:11,355 --> 00:56:11,980 of the lottery. 967 00:56:14,650 --> 00:56:16,020 And he's entitled. 968 00:56:20,150 --> 00:56:26,810 OK, so we're going to have these prices, rental rates and wage 969 00:56:26,810 --> 00:56:31,010 rates, normalizing the consumption good. 970 00:56:31,010 --> 00:56:33,800 OK, here's the insurance company thing. 971 00:56:38,620 --> 00:56:46,540 Basically, if you're working, you pay a premium ex post. 972 00:56:46,540 --> 00:56:52,530 And if you're not working, you get this indemnity. 973 00:56:56,180 --> 00:56:58,220 Well, I mean intuitively if you're working, 974 00:56:58,220 --> 00:57:03,440 you have more income, you kind contribute some back 975 00:57:03,440 --> 00:57:06,520 to the pool. 976 00:57:06,520 --> 00:57:10,760 But if an insurance company we're offering this, 977 00:57:10,760 --> 00:57:13,880 they would potentially make profits 978 00:57:13,880 --> 00:57:16,250 depending on the fraction of the people from whom they 979 00:57:16,250 --> 00:57:19,520 get the premium and the residual fraction 980 00:57:19,520 --> 00:57:21,920 to whom they pay the indemnity. 981 00:57:21,920 --> 00:57:24,140 If you have free entry into insurance, 982 00:57:24,140 --> 00:57:28,140 then this is going to drive this equation to zero. 983 00:57:28,140 --> 00:57:28,640 OK? 984 00:57:28,640 --> 00:57:32,030 So that's going to tie the premia and the indemnity 985 00:57:32,030 --> 00:57:40,005 to the probability or fraction of people working. 986 00:57:44,170 --> 00:57:47,172 So now, we're going to decentralize it. 987 00:57:47,172 --> 00:57:49,380 We're going to say look it's as if the household were 988 00:57:49,380 --> 00:57:54,860 maximizing expected utility, but as I said, voluntarily deciding 989 00:57:54,860 --> 00:57:57,800 whether to work for sure or not work at all or something 990 00:57:57,800 --> 00:57:59,240 in between. 991 00:57:59,240 --> 00:58:04,498 And then they're going to have this resource constraint. 992 00:58:07,250 --> 00:58:09,700 But I've now substituted in-- 993 00:58:19,330 --> 00:58:22,240 the x's entered into consumption. 994 00:58:22,240 --> 00:58:25,570 But the x's we're constrained by that zero profit condition. 995 00:58:25,570 --> 00:58:28,690 So we've substituted in the zero profit condition 996 00:58:28,690 --> 00:58:30,700 back into the household budget constraint 997 00:58:30,700 --> 00:58:33,790 and gotten this equation. 998 00:58:33,790 --> 00:58:35,410 Capital is equal to 1. 999 00:58:35,410 --> 00:58:38,250 So this thing's just going to go to 1 no matter what. 1000 00:58:38,250 --> 00:58:39,670 You're going to get a wage. 1001 00:58:39,670 --> 00:58:42,310 But you're basically going to be paid 1002 00:58:42,310 --> 00:58:45,670 the expected value of your pre-committed labor 1003 00:58:45,670 --> 00:58:47,950 participation. 1004 00:58:47,950 --> 00:58:49,240 I agree to be on call. 1005 00:58:49,240 --> 00:58:53,030 A hospital may call me. 1006 00:58:53,030 --> 00:58:55,280 I'm going to go to work if I get the call. 1007 00:58:55,280 --> 00:59:00,190 But my salary is based on whether I'm on call 1008 00:59:00,190 --> 00:59:02,200 all the time or not at all. 1009 00:59:02,200 --> 00:59:03,280 And I get to choose that. 1010 00:59:03,280 --> 00:59:06,940 Somehow that's the flexibility in the contract. 1011 00:59:06,940 --> 00:59:13,590 And this is the decentralized version with the household 1012 00:59:13,590 --> 00:59:14,460 optimization. 1013 00:59:14,460 --> 00:59:18,520 Firms maximize profits and markets clear. 1014 00:59:18,520 --> 00:59:21,173 That's where we're going to get the wage, the overall wage 1015 00:59:21,173 --> 00:59:22,090 and the interest rate. 1016 00:59:26,600 --> 00:59:28,600 So if you looked at the first order condition 1017 00:59:28,600 --> 00:59:33,230 to the consumer problem, you would see some obvious things 1018 00:59:33,230 --> 00:59:34,610 happening. 1019 00:59:34,610 --> 00:59:40,490 You're going to have a theta price, shadow price, 1020 00:59:40,490 --> 00:59:43,190 on the budget constraint that I just showed you. 1021 00:59:43,190 --> 00:59:48,300 And these probabilities are entering symmetrically 1022 00:59:48,300 --> 00:59:50,842 in utility and in consumption. 1023 00:59:50,842 --> 00:59:52,300 So when you take a derivative, they 1024 00:59:52,300 --> 00:59:54,850 are kind of like cancel out. 1025 00:59:54,850 --> 00:59:56,710 And so you get this. 1026 00:59:56,710 --> 01:00:00,220 But, look, here, they're going to cancel on both sides. 1027 01:00:00,220 --> 01:00:02,220 So theta is common. 1028 01:00:02,220 --> 01:00:04,807 So consumption has to be common. 1029 01:00:04,807 --> 01:00:07,140 So you're going to get full insurance on the consumption 1030 01:00:07,140 --> 01:00:08,100 side. 1031 01:00:08,100 --> 01:00:11,040 There's no reason to let consumption vary. 1032 01:00:11,040 --> 01:00:14,830 Remember, this was a separable utility function. 1033 01:00:14,830 --> 01:00:17,760 It was the utility of consumption plus-- 1034 01:00:17,760 --> 01:00:22,170 so why screw up the marginal utility of consumption? 1035 01:00:22,170 --> 01:00:25,830 You can get full smoothing out of on the consumption side. 1036 01:00:28,680 --> 01:00:31,920 So consumption is equal to each other, whether you work or not. 1037 01:00:35,790 --> 01:00:40,780 But that theme may not be at the boundary. 1038 01:00:40,780 --> 01:00:43,980 It could be interior. 1039 01:00:43,980 --> 01:00:48,430 So substituting a common consumption, 1040 01:00:48,430 --> 01:00:50,170 remembering disutility of work is 1041 01:00:50,170 --> 01:00:56,890 just m, you have this new optimization problem. 1042 01:00:56,890 --> 01:01:00,350 And this is equivalent with the other one. 1043 01:01:00,350 --> 01:01:02,360 Now, where's the aggregate elasticity? 1044 01:01:08,140 --> 01:01:10,180 What's the disutility of work? 1045 01:01:13,589 --> 01:01:14,563 AUDIENCE: Phi, right? 1046 01:01:17,490 --> 01:01:20,300 ROBERT TOWNSEND: It's linear. 1047 01:01:20,300 --> 01:01:26,170 It doesn't get any more easy to substitute than that. 1048 01:01:26,170 --> 01:01:30,470 See here it looks like you're choosing phi. 1049 01:01:30,470 --> 01:01:34,750 But the coefficient in front of it is just a number, m. 1050 01:01:34,750 --> 01:01:41,720 So phi is-- you know, why is phi look like hours? 1051 01:01:41,720 --> 01:01:44,570 Phi is the fraction of time you're working. 1052 01:01:44,570 --> 01:01:47,810 And if you work, you're working 1. 1053 01:01:47,810 --> 01:01:51,980 So total hours is like the fraction of the population 1054 01:01:51,980 --> 01:01:53,630 working. 1055 01:01:53,630 --> 01:01:57,560 That varies continuously-- this sort of pseudo representative 1056 01:01:57,560 --> 01:02:01,620 consumer thinks that it can choose any fraction it wants, 1057 01:02:01,620 --> 01:02:04,520 even though the underlying population cannot. 1058 01:02:04,520 --> 01:02:06,390 This is a stand in household. 1059 01:02:06,390 --> 01:02:07,640 It's not a real household. 1060 01:02:07,640 --> 01:02:11,720 But the aggregates that are predicted from this 1061 01:02:11,720 --> 01:02:16,460 will correspond to the underlying problem. 1062 01:02:16,460 --> 01:02:19,060 So that was the insight that Rogerson had. 1063 01:02:29,720 --> 01:02:32,240 And actually, I'm pretty sure it's also 1 to 1 1064 01:02:32,240 --> 01:02:34,040 with the right welfare. 1065 01:02:34,040 --> 01:02:37,700 You can use that aggregated utility 1066 01:02:37,700 --> 01:02:40,370 as a representation of the underlying welfare. 1067 01:02:40,370 --> 01:02:41,603 Why is that? 1068 01:02:41,603 --> 01:02:43,520 Well, even though you have all that diversity, 1069 01:02:43,520 --> 01:02:46,560 households are really alike in terms 1070 01:02:46,560 --> 01:02:47,820 of their utility functions. 1071 01:02:47,820 --> 01:02:50,460 So expected utility is the right metric. 1072 01:02:50,460 --> 01:02:52,020 And that's what that thing is. 1073 01:02:52,020 --> 01:02:54,720 It just looks funny when you write it down. 1074 01:02:58,720 --> 01:02:59,220 OK. 1075 01:03:15,860 --> 01:03:19,750 And then quickly, here's Hansen's version of it 1076 01:03:19,750 --> 01:03:27,080 with business cycles, going to the actual aggregate data. 1077 01:03:27,080 --> 01:03:33,400 As I said, total hours worked is hours 1078 01:03:33,400 --> 01:03:36,190 per person of those participating 1079 01:03:36,190 --> 01:03:39,870 times the number participating. 1080 01:03:39,870 --> 01:03:42,060 And then you take logs of it, basically. 1081 01:03:42,060 --> 01:03:44,350 And then you want to look at a variance. 1082 01:03:44,350 --> 01:03:47,310 You say the variance of a log of aggregate hours 1083 01:03:47,310 --> 01:03:49,420 has three components. 1084 01:03:49,420 --> 01:03:52,770 It's the variance of individual hours, the variance 1085 01:03:52,770 --> 01:03:56,970 of participation on the extensive margin 1086 01:03:56,970 --> 01:03:59,520 and this covariance term. 1087 01:03:59,520 --> 01:04:03,420 And in the US data, those are the numbers 1088 01:04:03,420 --> 01:04:07,690 consistent with that table that I showed you before. 1089 01:04:07,690 --> 01:04:09,780 So a lot of the variability in hours, 1090 01:04:09,780 --> 01:04:11,730 say over a business cycle or something, 1091 01:04:11,730 --> 01:04:13,688 has to do with varying participation 1092 01:04:13,688 --> 01:04:14,730 among individual members. 1093 01:04:20,200 --> 01:04:28,810 OK, so this is sort of familiar ingredients. 1094 01:04:28,810 --> 01:04:30,280 You'd have an aggregate production 1095 01:04:30,280 --> 01:04:32,330 function over hours in capital. 1096 01:04:32,330 --> 01:04:36,630 You have some Markov process on TFP. 1097 01:04:36,630 --> 01:04:43,050 You've seen this in the first part of this class as well. 1098 01:04:43,050 --> 01:04:44,370 Capital depreciates. 1099 01:04:44,370 --> 01:04:46,740 You can add to it with investment. 1100 01:04:46,740 --> 01:04:50,430 And you've got this utility function. 1101 01:04:50,430 --> 01:04:54,510 Again, this is like a Cobb-Douglas version, well, 1102 01:04:54,510 --> 01:04:56,610 logs off of a Cobb-Douglas version. 1103 01:04:59,770 --> 01:05:02,770 And the overall problem is to maximize 1104 01:05:02,770 --> 01:05:04,600 discounted expected utility. 1105 01:05:11,540 --> 01:05:15,410 Except we introduce this indivisibility. 1106 01:05:15,410 --> 01:05:18,950 So you can either work at h sub 0 hours 1107 01:05:18,950 --> 01:05:22,520 with some probability or 0. 1108 01:05:22,520 --> 01:05:29,070 Just like Rogerson with slightly different notation, 1109 01:05:29,070 --> 01:05:36,710 you'd get alpha T, say the probability of working or not 1110 01:05:36,710 --> 01:05:38,460 working. 1111 01:05:38,460 --> 01:05:41,660 You know, the way they've normalized it, the log of 1 1112 01:05:41,660 --> 01:05:42,440 is 0. 1113 01:05:42,440 --> 01:05:44,600 This thing is going to drop out. 1114 01:05:44,600 --> 01:05:46,490 And you'll get a utility function 1115 01:05:46,490 --> 01:05:50,795 over consumption and hours. 1116 01:05:54,970 --> 01:05:58,660 But remember, again, just to reiterate, 1117 01:05:58,660 --> 01:06:02,770 h0 is the fixed number of hours you have 1118 01:06:02,770 --> 01:06:05,490 to work if you work at all. 1119 01:06:05,490 --> 01:06:08,430 And alpha t is the fraction of the population that's 1120 01:06:08,430 --> 01:06:09,810 being assigned to work word. 1121 01:06:09,810 --> 01:06:13,530 Alpha, this coefficient in front of hours, 1122 01:06:13,530 --> 01:06:16,894 is the thing that's getting determined in equilibrium. 1123 01:06:25,430 --> 01:06:27,830 So after you make all those substitutions, 1124 01:06:27,830 --> 01:06:30,260 just like we did before with Rogerson's paper, 1125 01:06:30,260 --> 01:06:34,650 we end up with this pseudo utility 1126 01:06:34,650 --> 01:06:37,010 for the representative consumer. 1127 01:06:37,010 --> 01:06:42,550 And, yeah, again, it's linear in hours. 1128 01:06:42,550 --> 01:06:44,860 So depending on the wage relative to b, 1129 01:06:44,860 --> 01:06:49,570 it would look as if there's just enormous willingness 1130 01:06:49,570 --> 01:06:54,820 to supply labor, or elasticity, as you go from low wages 1131 01:06:54,820 --> 01:06:59,200 to high wages, you know, an enormous response. 1132 01:06:59,200 --> 01:07:01,240 It's just a review of what Rogerson did, 1133 01:07:01,240 --> 01:07:08,910 but it's in the context of this business cycle model. 1134 01:07:08,910 --> 01:07:12,210 So solve the first order conditions. 1135 01:07:12,210 --> 01:07:14,550 Compute the steady state. 1136 01:07:14,550 --> 01:07:18,210 Compute approximation to the steady state. 1137 01:07:18,210 --> 01:07:21,630 Solve for the law of motion of the endogenous variables. 1138 01:07:21,630 --> 01:07:23,940 And compute the moments. 1139 01:07:23,940 --> 01:07:27,240 Now, I don't want to belabor this, 1140 01:07:27,240 --> 01:07:30,870 because it would just take us too much time. 1141 01:07:30,870 --> 01:07:35,640 But we did models at the beginning of class 1142 01:07:35,640 --> 01:07:39,780 that featured occupation choice and development and so on. 1143 01:07:39,780 --> 01:07:42,300 This is like that in the sense that we 1144 01:07:42,300 --> 01:07:46,215 have an attempt to match data. 1145 01:07:46,215 --> 01:07:47,590 In this case, in this literature, 1146 01:07:47,590 --> 01:07:49,300 it happens to be business cycle data. 1147 01:07:49,300 --> 01:07:54,260 But you're going to see Seema's version of it in a moment. 1148 01:07:54,260 --> 01:07:56,830 So the cool thing is you've got this machine. 1149 01:07:56,830 --> 01:07:58,470 You've got this model. 1150 01:07:58,470 --> 01:08:01,690 And if you're willing to take a stand on parameters that you 1151 01:08:01,690 --> 01:08:04,990 observe in data or calibrate other parameters, 1152 01:08:04,990 --> 01:08:08,090 you can generate time series from the model. 1153 01:08:08,090 --> 01:08:10,900 And you can compare the time series 1154 01:08:10,900 --> 01:08:13,710 to what you see in the data. 1155 01:08:13,710 --> 01:08:17,290 And this is the algorithm for solving the model. 1156 01:08:17,290 --> 01:08:20,500 Again, I'm not going to belabor this. 1157 01:08:20,500 --> 01:08:24,819 You know, they pick capital share and depreciation rates 1158 01:08:24,819 --> 01:08:38,470 and discount rates and so on and so forth and generate the data. 1159 01:08:38,470 --> 01:08:40,689 Now, they're two economies here. 1160 01:08:40,689 --> 01:08:44,470 This one with divisible labor, this one 1161 01:08:44,470 --> 01:08:47,229 that we featured with indivisible labor. 1162 01:08:47,229 --> 01:08:53,330 And you might want to look at the variability of output 1163 01:08:53,330 --> 01:08:54,710 consumption and hours. 1164 01:08:54,710 --> 01:08:57,080 This is the variability of ours in the data. 1165 01:09:00,350 --> 01:09:05,109 This is the variability of hours without the indivisibility. 1166 01:09:05,109 --> 01:09:07,600 This is the variability of hours with it. 1167 01:09:07,600 --> 01:09:10,750 Now, they didn't get it all the way up to 1.66. 1168 01:09:10,750 --> 01:09:13,479 But they're certainly dominating 0.70. 1169 01:09:13,479 --> 01:09:16,149 So that, you know, as I keep saying, 1170 01:09:16,149 --> 01:09:19,029 these economies with certain kinds of indivisibilities 1171 01:09:19,029 --> 01:09:21,939 are able to increase the responsiveness 1172 01:09:21,939 --> 01:09:26,944 of aggregate hours to wages, more consistent with what 1173 01:09:26,944 --> 01:09:27,444 we see. 1174 01:09:27,444 --> 01:09:28,320 Yeah, Matt. 1175 01:09:28,320 --> 01:09:32,069 AUDIENCE: Is this economy with individual labor, 1176 01:09:32,069 --> 01:09:33,080 is it actually-- 1177 01:09:33,080 --> 01:09:34,622 like one of your student simulation-- 1178 01:09:34,622 --> 01:09:37,290 is it identical to the RBC model except the utility function? 1179 01:09:37,290 --> 01:09:38,560 ROBERT TOWNSEND: Yeah. 1180 01:09:38,560 --> 01:09:40,310 Well, except for the indivisibility, yeah. 1181 01:09:44,880 --> 01:09:47,340 AUDIENCE: When you have the utility function with 1182 01:09:47,340 --> 01:09:50,125 indivisibility, when you have like the reduced form, 1183 01:09:50,125 --> 01:09:50,750 because don't-- 1184 01:09:50,750 --> 01:09:55,712 I mean, in fact, again you've got phi or the proportion 1185 01:09:55,712 --> 01:09:59,603 of time work-- 1186 01:09:59,603 --> 01:10:01,270 ROBERT TOWNSEND: That's what's going on. 1187 01:10:01,270 --> 01:10:03,020 See, there are two economies here and kind 1188 01:10:03,020 --> 01:10:04,450 of two ways of doing business. 1189 01:10:04,450 --> 01:10:07,990 You could go to the micro data, look at individual labor 1190 01:10:07,990 --> 01:10:11,080 supply, try to populate the economy 1191 01:10:11,080 --> 01:10:14,650 with some fresh elasticity that you observe in the data 1192 01:10:14,650 --> 01:10:17,290 and then go through all the steps. 1193 01:10:17,290 --> 01:10:19,720 Or you could say, no, no, no, no, 1194 01:10:19,720 --> 01:10:22,460 you either work or you don't work, 1195 01:10:22,460 --> 01:10:26,230 get that pseudo household. 1196 01:10:26,230 --> 01:10:31,350 And it's going to generate its own elasticity 1197 01:10:31,350 --> 01:10:33,660 and redo the simulations. 1198 01:10:33,660 --> 01:10:36,885 And that's what's getting compared here. 1199 01:10:36,885 --> 01:10:37,795 Yep. 1200 01:10:37,795 --> 01:10:41,380 AUDIENCE: Compared to the response of working hours 1201 01:10:41,380 --> 01:10:44,020 is totally driven by the extensive margin. 1202 01:10:44,020 --> 01:10:46,090 ROBERT TOWNSEND: Yes. 1203 01:10:46,090 --> 01:10:47,800 AUDIENCE: If you also want to match 1204 01:10:47,800 --> 01:10:52,320 the elasticity of this extensive margin, maybe-- 1205 01:10:52,320 --> 01:10:56,010 ROBERT TOWNSEND: Yes, I'll show you another paper where-- 1206 01:10:56,010 --> 01:10:58,330 so this is too extreme. 1207 01:10:58,330 --> 01:11:01,780 But it shows how to get-- 1208 01:11:01,780 --> 01:11:06,600 OK, so this is Kim. 1209 01:11:06,600 --> 01:11:09,250 I'll take you through this really quickly. 1210 01:11:09,250 --> 01:11:12,750 But it does link up to the incomplete market literature 1211 01:11:12,750 --> 01:11:15,180 that we talked about last time. 1212 01:11:15,180 --> 01:11:19,340 And the point is you can generate a higher 1213 01:11:19,340 --> 01:11:22,610 aggregate elasticity than what you see in the data 1214 01:11:22,610 --> 01:11:26,690 without assuming all this stuff with complete markets 1215 01:11:26,690 --> 01:11:28,650 and the lotteries. 1216 01:11:28,650 --> 01:11:30,480 So in other words, there's something 1217 01:11:30,480 --> 01:11:34,420 crucial about the aggregation, which is more limited here. 1218 01:11:34,420 --> 01:11:36,420 We're not going to get as high a number. 1219 01:11:36,420 --> 01:11:43,920 But we are going to get a higher aggregate elasticity than what 1220 01:11:43,920 --> 01:11:45,750 you would think if you just looked, 1221 01:11:45,750 --> 01:11:48,330 as Yeng was saying really, if you just 1222 01:11:48,330 --> 01:11:51,180 looked at the micro data. 1223 01:11:51,180 --> 01:11:52,950 This is a nice paper-- 1224 01:11:52,950 --> 01:11:56,220 I wasn't aware of it till a few months ago actually-- 1225 01:11:56,220 --> 01:11:58,380 because they're really into the details 1226 01:11:58,380 --> 01:12:00,960 of the cross-sectional earnings and wealth distribution. 1227 01:12:00,960 --> 01:12:04,050 They're really looking at the micro data. 1228 01:12:04,050 --> 01:12:07,760 Whereas those macro guys, at most, 1229 01:12:07,760 --> 01:12:09,410 are borrowing a few parameters. 1230 01:12:14,340 --> 01:12:19,770 You've got males and females, like a two-member household, 1231 01:12:19,770 --> 01:12:22,920 maximizing expected discounted utility. 1232 01:12:22,920 --> 01:12:27,400 This is again this Cobb-Douglass type specification. 1233 01:12:27,400 --> 01:12:28,950 This is at the aggregate household 1234 01:12:28,950 --> 01:12:35,180 level for some reason already aggregated with these weights. 1235 01:12:35,180 --> 01:12:37,470 So it's male hours and female hours. 1236 01:12:42,280 --> 01:12:47,200 Gamma is the sort of degree of inter-temporal sub-elasticity 1237 01:12:47,200 --> 01:12:49,660 that we care so much about. 1238 01:12:49,660 --> 01:12:53,357 And now, they're going to be serious micro guys, 1239 01:12:53,357 --> 01:12:55,315 and they're going to actually look in the data, 1240 01:12:55,315 --> 01:13:00,640 at male and female wages and impute productivity. 1241 01:13:00,640 --> 01:13:03,340 So these x things-- 1242 01:13:03,340 --> 01:13:06,730 there's going to be one for males and one for females-- 1243 01:13:06,730 --> 01:13:10,360 take hours and multiply by productivities. 1244 01:13:10,360 --> 01:13:14,630 And these productivities can move around over time. 1245 01:13:14,630 --> 01:13:17,440 So it's not just a firm having TFP that's moving around. 1246 01:13:17,440 --> 01:13:21,380 It's households having labor productivity 1247 01:13:21,380 --> 01:13:22,300 that's moving around. 1248 01:13:25,173 --> 01:13:26,590 And the household is going to have 1249 01:13:26,590 --> 01:13:30,630 this sort of standard incomplete markets budget constraints. 1250 01:13:30,630 --> 01:13:34,720 So this looks a lot like what we had last time sort of. 1251 01:13:34,720 --> 01:13:36,970 They're going to have assets in the previous period 1252 01:13:36,970 --> 01:13:38,440 and interest on that. 1253 01:13:38,440 --> 01:13:42,490 They can save to take into the following period. 1254 01:13:42,490 --> 01:13:44,770 And the household, as a whole, is 1255 01:13:44,770 --> 01:13:48,130 going to have wage earnings as a function of hours. 1256 01:13:48,130 --> 01:13:49,480 Now, we have labor supply. 1257 01:13:49,480 --> 01:13:53,590 We didn't have that last Tuesday. 1258 01:13:53,590 --> 01:13:56,140 And there's, say, a bound on assets. 1259 01:13:56,140 --> 01:13:58,810 This could be zero, no borrowing. 1260 01:13:58,810 --> 01:14:02,170 It could be a negative number, a limit on borrowing. 1261 01:14:02,170 --> 01:14:06,100 Just like the standard incomplete markets lecture 1262 01:14:06,100 --> 01:14:09,580 from last time, we give them an aggregate Cobb-Douglas 1263 01:14:09,580 --> 01:14:11,780 technology. 1264 01:14:11,780 --> 01:14:16,535 And we solve this forward-looking value function. 1265 01:14:20,800 --> 01:14:22,420 So it's a bit bewildering. 1266 01:14:22,420 --> 01:14:26,780 But they're both working. 1267 01:14:26,780 --> 01:14:28,180 This e is not we. 1268 01:14:28,180 --> 01:14:29,290 It's like wee. 1269 01:14:29,290 --> 01:14:33,100 No, ee means employed employed, employed not 1270 01:14:33,100 --> 01:14:37,810 employed, et cetera, depending on the female and male members. 1271 01:14:37,810 --> 01:14:40,810 And this is the case where currently they're 1272 01:14:40,810 --> 01:14:43,660 both employed. 1273 01:14:43,660 --> 01:14:47,020 Solving for assets, you know, anticipating 1274 01:14:47,020 --> 01:14:50,530 that they'll decide on their work status next time. 1275 01:14:50,530 --> 01:14:54,850 Now, again, you can see this extensive margin here 1276 01:14:54,850 --> 01:14:59,050 is playing a big role, deciding member by member 1277 01:14:59,050 --> 01:15:02,280 whether it will be working or not. 1278 01:15:02,280 --> 01:15:06,700 And at least in the '50s, this was a big issue, 1279 01:15:06,700 --> 01:15:10,030 increasing female labor force participation. 1280 01:15:10,030 --> 01:15:11,740 Things have settled down now. 1281 01:15:11,740 --> 01:15:13,060 It's much more symmetric. 1282 01:15:16,280 --> 01:15:18,200 But the wife did not always stay home. 1283 01:15:18,200 --> 01:15:21,140 Sometimes they participated, depending 1284 01:15:21,140 --> 01:15:22,560 on the household situation. 1285 01:15:22,560 --> 01:15:30,600 So family labor supply, and what do I want to say here? 1286 01:15:30,600 --> 01:15:33,270 So not much. 1287 01:15:33,270 --> 01:15:37,840 It looks more complicated than it is. 1288 01:15:37,840 --> 01:15:45,320 You have this all for a steady state, which is complicated. 1289 01:15:45,320 --> 01:15:47,310 Someone asked me-- who was it? 1290 01:15:47,310 --> 01:15:51,433 Can't remember-- about adding state variables. 1291 01:15:51,433 --> 01:15:53,600 So here, you know, we have a lot of state variables. 1292 01:15:53,600 --> 01:15:55,140 We've got male productivity. 1293 01:15:55,140 --> 01:15:56,930 We've got female productivity. 1294 01:15:56,930 --> 01:15:59,000 We have the distribution of wealth. 1295 01:15:59,000 --> 01:16:00,500 All these things have distributions 1296 01:16:00,500 --> 01:16:03,190 in the population. 1297 01:16:03,190 --> 01:16:06,890 And we have the sort of shock in the aggregate production 1298 01:16:06,890 --> 01:16:07,390 function. 1299 01:16:11,040 --> 01:16:14,060 So they're going to do what those macro guys do, 1300 01:16:14,060 --> 01:16:16,020 which is just look in the steady state. 1301 01:16:16,020 --> 01:16:18,080 They have to compute it. 1302 01:16:18,080 --> 01:16:20,420 And then they're going to look at very-- 1303 01:16:20,420 --> 01:16:23,390 there's no time subscripts on the wages and interest rates, 1304 01:16:23,390 --> 01:16:25,730 because you're in a steady state, where 1305 01:16:25,730 --> 01:16:28,790 all this distribution stuff has settled down. 1306 01:16:28,790 --> 01:16:31,970 You have a lot of churning from one status 1307 01:16:31,970 --> 01:16:35,060 to another within the steady state. 1308 01:16:35,060 --> 01:16:37,760 So individuals and households are experiencing 1309 01:16:37,760 --> 01:16:40,670 different things over time. 1310 01:16:40,670 --> 01:16:44,300 But the economy wide wages and interest rates 1311 01:16:44,300 --> 01:16:45,980 have settled down to constants. 1312 01:16:49,080 --> 01:16:55,370 And I'll skip-- they actually start estimating parameters 1313 01:16:55,370 --> 01:16:57,500 with the micro data. 1314 01:16:57,500 --> 01:17:05,930 And, you know, their goal here is 1315 01:17:05,930 --> 01:17:09,830 to get this aggregate elasticity high, 1316 01:17:09,830 --> 01:17:13,100 higher than you would see as they 1317 01:17:13,100 --> 01:17:14,900 estimate from the micro data. 1318 01:17:14,900 --> 01:17:18,320 So, Yeng, that's a little better example 1319 01:17:18,320 --> 01:17:21,890 of actually looking at the underlying micro data 1320 01:17:21,890 --> 01:17:26,940 and still using this sort of macro aggregation. 1321 01:17:26,940 --> 01:17:28,670 Yep? 1322 01:17:28,670 --> 01:17:32,170 AUDIENCE: Still saying that from micro data 1323 01:17:32,170 --> 01:17:36,243 the elasticity, so it's made to be smaller. 1324 01:17:36,243 --> 01:17:37,160 ROBERT TOWNSEND: Yeah. 1325 01:17:37,160 --> 01:17:38,290 Yeah. 1326 01:17:38,290 --> 01:17:40,550 AUDIENCE: Like even though you have model, it just-- 1327 01:17:40,550 --> 01:17:41,800 ROBERT TOWNSEND: That's right. 1328 01:17:41,800 --> 01:17:44,180 So why is it still happening? 1329 01:17:44,180 --> 01:17:46,100 Because, again, there's this indivisibility 1330 01:17:46,100 --> 01:17:50,164 going on about whether or not to work. 1331 01:17:50,164 --> 01:17:55,440 AUDIENCE: So if you incorporate indivisibility, then-- 1332 01:17:55,440 --> 01:17:57,830 because I thought that point of Cheng 1333 01:17:57,830 --> 01:18:03,180 is that if you look at the extensive margin, 1334 01:18:03,180 --> 01:18:05,130 that's still like very small compared 1335 01:18:05,130 --> 01:18:09,964 to what the macro model would be in individual labor. 1336 01:18:13,700 --> 01:18:16,550 ROBERT TOWNSEND: Yeah, again, at the individual level, 1337 01:18:16,550 --> 01:18:18,867 you'll back out certain low elasticities. 1338 01:18:18,867 --> 01:18:20,450 But the point of this whole literature 1339 01:18:20,450 --> 01:18:23,540 is when you aggregate up and look 1340 01:18:23,540 --> 01:18:27,230 at how aggregated hours are moving around, 1341 01:18:27,230 --> 01:18:28,910 you can get bigger numbers. 1342 01:18:28,910 --> 01:18:30,370 It's not inconsistent. 1343 01:18:34,190 --> 01:18:38,790 Which brings me very briefly, although fortunately, I've 1344 01:18:38,790 --> 01:18:44,560 said a few words about this, Seema's paper 1345 01:18:44,560 --> 01:18:49,460 looks at productivity shots in agriculture And, looks at what 1346 01:18:49,460 --> 01:18:50,405 happens to wages. 1347 01:18:54,510 --> 01:18:57,100 Now, you know, think about a supply curve 1348 01:18:57,100 --> 01:18:58,390 and a varying demand curve. 1349 01:18:58,390 --> 01:19:01,350 So it rains a lot or a little, that kind 1350 01:19:01,350 --> 01:19:03,150 of affects productivity. 1351 01:19:03,150 --> 01:19:05,880 That's moving the demand for labor. 1352 01:19:05,880 --> 01:19:08,760 If the supply curve is inelastic, 1353 01:19:08,760 --> 01:19:11,970 you're going to get a high variability in the wage. 1354 01:19:11,970 --> 01:19:13,470 Her point is she cares. 1355 01:19:13,470 --> 01:19:17,370 The workers get hurt a lot when there are droughts 1356 01:19:17,370 --> 01:19:20,160 and it doesn't rain because the wage drops. 1357 01:19:20,160 --> 01:19:22,530 Landowners love it. 1358 01:19:22,530 --> 01:19:27,510 Their output is lower, but they have less of a wage bill. 1359 01:19:27,510 --> 01:19:32,430 And then she couples that with assumptions about how well 1360 01:19:32,430 --> 01:19:36,990 or how poorly the banking system is. 1361 01:19:36,990 --> 01:19:40,950 So I'll just tell you in words, she 1362 01:19:40,950 --> 01:19:45,650 has a 2-period problem, which she thinks is enough, rightly, 1363 01:19:45,650 --> 01:19:47,870 to get what she wants. 1364 01:19:47,870 --> 01:19:49,530 She has people forward looking. 1365 01:19:49,530 --> 01:19:52,100 So they're solving 2-period problems. 1366 01:19:52,100 --> 01:19:55,220 And then you decide whether or not to save 1367 01:19:55,220 --> 01:19:59,330 or to borrow based on your current situation. 1368 01:19:59,330 --> 01:20:03,590 She's saying that if they can borrow and save 1369 01:20:03,590 --> 01:20:05,630 in the banking system is good, they're 1370 01:20:05,630 --> 01:20:13,430 going to be less needing to work in a bad agricultural year, 1371 01:20:13,430 --> 01:20:16,970 because they can borrow instead of working harder. 1372 01:20:16,970 --> 01:20:19,730 So this is an incomplete markets model 1373 01:20:19,730 --> 01:20:25,310 with limitations and regional variation in the banking system 1374 01:20:25,310 --> 01:20:30,080 that is focused on how much wages move around 1375 01:20:30,080 --> 01:20:32,795 with productivity agricultural productivity shocks. 1376 01:20:35,800 --> 01:20:41,160 Now, her paper is qualitative in the sense that she shows that 1377 01:20:41,160 --> 01:20:44,370 there is with less what she called wage elasticity-- 1378 01:20:44,370 --> 01:20:47,670 there's less responsiveness of wage to rainfall shocks 1379 01:20:47,670 --> 01:20:50,930 or instrumented productivity shocks-- 1380 01:20:50,930 --> 01:20:52,520 the better the banking system is. 1381 01:20:52,520 --> 01:20:54,360 That's what she cares about. 1382 01:20:54,360 --> 01:20:57,650 Now, interestingly, she doesn't get into the details 1383 01:20:57,650 --> 01:20:59,700 of the numbers. 1384 01:20:59,700 --> 01:21:03,970 How quantitatively big or small is this response? 1385 01:21:03,970 --> 01:21:05,580 So she doesn't do anything wrong. 1386 01:21:05,580 --> 01:21:07,860 It's actually a very nice paper. 1387 01:21:07,860 --> 01:21:12,630 But if she were seriously trying to estimate the elasticities, 1388 01:21:12,630 --> 01:21:15,630 she would need to take into account 1389 01:21:15,630 --> 01:21:19,410 whether there is this extensive margin participation. 1390 01:21:19,410 --> 01:21:21,450 And the aggregate level elasticities 1391 01:21:21,450 --> 01:21:28,560 could be lower than they might seem to be as in the two papers 1392 01:21:28,560 --> 01:21:31,450 that we just covered. 1393 01:21:31,450 --> 01:21:33,060 So again, nothing wrong. 1394 01:21:33,060 --> 01:21:35,970 But, you know, when you're in practice and development work 1395 01:21:35,970 --> 01:21:38,340 and you're thinking not just about individual responses, 1396 01:21:38,340 --> 01:21:41,340 but sort of collective responses and whole regions, 1397 01:21:41,340 --> 01:21:44,970 and so on then these sort of tricks that we get, 1398 01:21:44,970 --> 01:21:49,930 lessons learned from the macro literature 1399 01:21:49,930 --> 01:21:53,080 are very helpful in combining the macro and micro data. 1400 01:21:56,650 --> 01:21:59,380 So you can read the details of the slides. 1401 01:21:59,380 --> 01:22:02,460 But I basically covered it. 1402 01:22:02,460 --> 01:22:04,340 Thank you.