library(foreign)
oind <- read.dta("https://teaching.sociology.ul.ie/so5032/oind.dta")
round(cor(oind[,c("Income", "Hours")]), digits=3)

library(ggplot2)
library(GGally)
ggpairs(oind[,c("Income", "JobScore", "Hours")], mapping = ggplot2::aes(alpha = 0.1))

t.test(oind$Income ~ oind$Gender, var.equal=TRUE)

summary(mod2 <- lm(data=oind, Income ~ Hours))

summary(mod3 <- lm(data=oind, Income ~ Gender))

summary(mod4a <- lm(data=subset(oind, Gender=="male"), Income ~ Hours))

summary(mod4b <- lm(data=subset(oind, Gender=="female"), Income ~ Hours))

summary(mod4c <- lm(data=oind, Income ~ Gender*Hours))

indir <- read.dta("https://teaching.sociology.ul.ie/so5032/indirect.dta")
summary(reg5 <- lm(data=indir,  ownscore ~ fatherscore))

summary(reg5b <- lm(data=indir,  education ~ fatherscore))

summary(reg5c <- lm(data=indir, ownscore ~ education))

summary(reg5d <- lm(data=indir, ownscore ~ education + fatherscore))