###### Code from examples worked in class
######

## California governor X^2 example
recall <- c(46.7, 20.1, 8, 25.2)
seats <- c(45.8, 33.1, 10.2, 10.9)
seats.prop <- seats / sum(seats)
expected <- 100 * seats.prop
1 - pchisq(chi2, df=4-1)
1 - pchisq(chi2, df=4-1)
# compare to:
chisq.test(recall, p=seats.prop, correct=FALSE)
chisq.test(recall, p=seats.prop)
cbind(poll/787*100, actual)

## Democracy and war example
x <- matrix(c(40,74,3,11), nrow=2, byrow=T)
colnames(x) <- c("Democracy", "Dictatorship")
rownames(x) <- c("Peace", "War")
chisq.test(x)

## Fisher exact test on Dem & War example
fisher.test(x)
# compare to:
chisq.test(x, simulate=TRUE)

## Democraticness pre- v. post-1945
free <- matrix(byrow=T, nrow=2, c(17, 8, 6, 6, 11, 9, 3, 1, 6, 9, 8, 17, 21, 6))
rownames(free) <- c("Pre45", "Post45")
colnames(free) <- 1:7
free
chisq.test(free)

## Convert previous example to a dataset format
yearf <- factor(year, labels=c("Pre","post"))
freedom <- c(rep(1,17), rep(2,8), rep(3,6), rep(4,6),rep(5,11),rep(6,9),rep(7,3),
             rep(1,1), rep(2,6), rep(3,9), rep(4,8),rep(5,17),rep(6,21),rep(7,6))
df <- data.frame(yearf,freedom)
table(df)
t.test(freedom ~ yearf)  # violates the t-test assumptions!
wilcox.test(freedom ~ yearf)
median(df$freedom[df$yearf=="Pre"])
median(df$freedom[df$yearf=="post"])