if (FALSE) #Make Romeo slide (Bayesian update, continuous-continuous 1) { makepdf = FALSE theta1 = seq(0,.4,.01) theta2 = seq(.4,1,.01) pr1 = 0*theta1 + 1 pr2 = 0*theta2 + 1 T = 21/8 post1 = 0*theta1 post2 = 1/(T*theta2^3) if (makepdf) { fname = '../pdftex/img/class21-1.pdf' pdf(file=fname, width=3, height=2) par(mar=c(2,2,1.7,.3)) } title = expression(paste('Prior and posterior for ',theta)) plot(c(0,1),c(0,max(post2)), type='n', xlab='', ylab='', main=title,cex.main=1.4,cex.lab=1.3, cex.axis = 1) lines(c(theta1,theta2), c(pr1,pr2), col='red', lwd=2) lines(c(theta1,theta2), c(post1,post2), col='cyan', lwd=2) abline(h=0) if (makepdf) dev.off() } if (FALSE) #Make waiting times 1 slide (Bayesian update, continuous-continuous 2) { makepdf = FALSE lambda = seq(0,2.5,.01) pr = 2*exp(-2*lambda) T = 4/125 post = (2/T)*lambda^2*exp(-5*lambda) if (makepdf) { fname = '../pdftex/img/class21-2.pdf' pdf(file=fname, width=3, height=2) par(mar=c(2,2,1.7,.3)) } title = expression(paste('Prior and posterior for ',lambda)) plot(c(0,max(lambda)),c(0,max(pr)), type='n', xlab='', ylab='', main=title,cex.main=1.4,cex.lab=1.3, cex.axis = 1) lines(lambda, pr, col='red', lwd=2) lines(lambda, post, col='cyan', lwd=2) abline(h=0) if (makepdf) dev.off() } if (FALSE) #ANOVA question { #DATA ---- T1 = c(6,8,4,5,3,4) T2 = c(8,12,9,11,6,8) T3 = c(13,9,11,8,7,12) #One way ANOVA using aov() ---- treat = c(rep('T1',length(T1)),rep('T2',length(T2)),rep('T3',length(T3))) recovery = c(T1,T2,T3) data.recovery = data.frame(treat,recovery) print(data.recovery) aov.data = aov(recovery~treat,data=data.recovery) #do the analysis of variance summary(aov.data) #show the summary table print(model.tables(aov.data,"means"),digits=3) #report the means and the number of subjects/cell boxplot(recovery~treat,data=data.recovery)#graphical summarydatafilename # One way ANOVA by hand ---- # Make sure all the groups are the same size if (length(T1) != length(T2) || length(T2) != length(T3)) stop("lengths are not equal", call. = F) m = length(T1) n = 3 group.means = c(mean(T1),mean(T2), mean(T3)) grandmean = mean(group.means) group.vars = c(var(T1),var(T2), var(T3)) betweenGroupVar = m*var(group.means) aveWithinGroupVar = mean(group.vars) fstat = betweenGroupVar/aveWithinGroupVar p = 1-pf(fstat, n-1,n*(m-1)) print(paste('Group means',toString(group.means))) print(paste('Grandmean',grandmean)) print(paste('Group vars', toString(group.vars))) print(paste('Between group var', betweenGroupVar)) print(paste('Within group var', aveWithinGroupVar)) print(paste('fstat',fstat)) print(paste('p',p)) }