Recall the Titanic Data.csv data associated with the “Sinking of the RMS Titanic”
titanic.df <- read.csv(paste("Titanic Data.csv", sep=""))
Creating a table showing the average age of the survivors and the average age of the people who died.
titanic.df$Survived = factor(titanic.df$Survived, levels = c(0,1), labels = c("no", "yes"))
aggregate(titanic.df$Age, by=list(Survived=titanic.df$Survived), mean)
## Survived x
## 1 no 30.41530
## 2 yes 28.42382
Run a t-test to test the following hypothesis: H2: The Titanic survivors were younger than the passengers who died.
t.test(Age~Survived, data=titanic.df)
##
## Welch Two Sample t-test
##
## data: Age by Survived
## t = 2.1816, df = 667.56, p-value = 0.02949
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
## 0.1990628 3.7838912
## sample estimates:
## mean in group no mean in group yes
## 30.41530 28.42382
As the value of p is less than 0.05 we reject null hypothesis and conclude that there is significant difference between the two means and “that the Titanic survivors were younger than the passengers who died”.