## Seminar 6. Hypothesis testing ## # load Titanic dataset via link & delete NAs df <- read.csv("https://raw.githubusercontent.com/allatambov/Py-programming-3/master/28-05/Titanic.csv") df <- na.omit(df) # select only survived passengers surv <- df[df$Survived == 1, ] # t-test for one mean mean(surv$Age) t.test(surv$Age, mu = 30) t.test(surv$Age, mu = 30, alternative = "less") # H1: mu < 30 # t-test for two means t.test(surv$Age ~ surv$Sex) t.test(surv$Age ~ surv$Sex, alternarive = "greater") # H1: mu1 > mu2