#----------------------------
# Problem 2ab
#source('http://web.mit.edu/jorloff/www/18.05/r-code/ps3prob2data.r')
source('ps3prob2data.r')
years = getprob2data()
mean(years)
sqrt(var(years))
hist(years,freq=T,breaks=seq(0,5,.1), main= "Years of Survival", col="yellow")
#Export plot as pdf from RStudio

#-----------------------------
# Problem 4bc. 
# PDF plot
h1 = seq(0,30,.01)
g1 = (40-h1)/750
G1 = 40*h1/750 - h1^2/1500
h = c(0,30)
g = c(0,5/75)
# type='n' means no plot. We just use it to establish dimensions
plot(h,g,type='n', main="PDF: g(h) vs. h",axes=F)
# Draw the axes. pos=0 means place where x=0 or y = 0
axis(1,pos=0,col='black')
axis(2,pos=0,col='black')
lines(h1,g1,lwd=2, col='blue')
#Export plot from RStudio

# CDF plot
h = c(0,30)
G = c(0,1)
plot(h,G,type='n', main="CDF: G(h) vs h",axes=F)
axis(1,pos=0,col='black')
axis(2,pos=0,col='black')
lines(h1,G1,lwd=2, col='blue')
#Export plot from RStudio

#------------------------
# Problem 6a
# Plot Norm(280, 8.5^2)
# We'll plot 3 standard deviations
m = 280
s = 8.5
x1 = seq(250,305,.01)
f1 = dnorm(x1,m,s)
F1 = pnorm(x1,m,s)
x = c(250,305)
f = c(0,1.1*max(f1))
# type='n' means no plot. We just use it to establish dimensions
# For some reason axes=F generates a warning, but plot does the right thing
plot(x,f,type='n', main="PDF: f(x) vs. x",axes=F)
# Draw the axes. pos=0 means place where x=0 or y = 0
axis(1,pos=0,col='black')
axis(2,pos=250,col='black')
lines(x1,f1,lwd=2, col='blue')
#Export plot from RStudio

# CDF plot
F = c(0,1)
# For some reason axes=F generates a warning, but plot does the right thing
plot(x,F,type='n', main="CDF: F(x) vs x",axes=F)
axis(1,pos=0,col='black')
axis(2,pos=250,col='black')
lines(x1,F1,lwd=2, col='blue')
#Export plot from RStudio


#------------------------