Dean.df <- read.csv(paste("DeansDilemma.csv", sep = ""))
placed.df<-Dean.df[which(Dean.df$Placement_B== 1),]
mean.salary <- aggregate(Salary ~ Gender, data= placed.df,mean )
mean.salary
## Gender Salary
## 1 F 253068.0
## 2 M 284241.9
mean(placed.df$Salary[placed.df$Gender=="M"])
## [1] 284241.9
mean(placed.df$Salary[placed.df$Gender=="F"])
## [1] 253068
library(MASS)
library(psych)
t.test(Salary ~ Gender, data=placed.df)
##
## Welch Two Sample t-test
##
## data: Salary by Gender
## t = -3.0757, df = 243.03, p-value = 0.00234
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
## -51138.42 -11209.22
## sample estimates:
## mean in group F mean in group M
## 253068.0 284241.9
P-value is 0.00234
All the calculation depends on the p-value which is very less (i.e p<0.05) so we will reject the null hypothesis.