This assignment is based on the case study of Dean’s Dilemma and it is in 6 parts:
1.Submit your R code that creates a table showing the mean salary of males and females, who were placed.
2.What is the average salary of male MBAs who were placed?
3.What is the average salary of female MBAs who were placed?
4.Submit R code to run a t-test for the Hypothesis “The average salary of the male MBAs is higher than the average salary of female MBAs.”
5.What is the p-value based on the t-test?
6.Please interpret the meaning of the t-test, as applied to the average salaries of male and female MBAs.
deansdilemma.df <- read.csv(paste("Data - Deans Dilemma.csv", sep=""))
View(deansdilemma.df)
placed.df<-deansdilemma.df[which(deansdilemma.df$Placement_B==1),]
View(placed.df)
aggregate(placed.df$Salary, by=list(Gender=placed.df$Gender),mean)
## Gender x
## 1 F 253068.0
## 2 M 284241.9
male.df<-placed.df[which(placed.df$Gender.B==0),]
View(male.df)
mean(male.df$Salary)
## [1] 284241.9
female.df<-placed.df[which(placed.df$Gender.B==1),]
View(female.df)
mean(female.df$Salary)
## [1] 253068
aggregate(placed.df$Salary, by=list(placed.df$Gender), FUN=mean)
## Group.1 x
## 1 F 253068.0
## 2 M 284241.9
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
the p-value based on the t-test is 0.00234.
Based on the above output of the t-test, we can not reject the hypothesis that “The average salary of the male MBAs is higher than the average salary of female MBAs.” (p>0.001)