1. Average Monthly Hours vs Left

t-test

## 
##  Welch Two Sample t-test
## 
## data:  hr$average_montly_hours by hr$left
## t = -7.5323, df = 4875.1, p-value = 5.907e-14
## alternative hypothesis: true difference in means between group Stayed and group Left is not equal to 0
## 95 percent confidence interval:
##  -10.534631  -6.183384
## sample estimates:
## mean in group Stayed   mean in group Left 
##             199.0602             207.4192

Technical Interpretation

Reject the Ho, p-value < 0.01, there is a difference in means, where employees who left had more average monthly hours

Non-Technical Interpretation

Employees that left worked more hours

Graph

2. Number of Projects vs Left

t-test

## 
##  Welch Two Sample t-test
## 
## data:  hr$number_project by hr$left
## t = -2.1663, df = 4236.5, p-value = 0.03034
## alternative hypothesis: true difference in means between group Stayed and group Left is not equal to 0
## 95 percent confidence interval:
##  -0.131136535 -0.006540119
## sample estimates:
## mean in group Stayed   mean in group Left 
##             3.786664             3.855503

Technical Interpretation

Retain the Ho, p-value > 0.01, there is no difference in means of number of projects

Non-Technical Interpretation

Employees who left had no difference in number of projects

Graph

3. Time Spent at Company vs Left

t-test

## 
##  Welch Two Sample t-test
## 
## data:  hr$time_spend_company by hr$left
## t = -22.631, df = 9625.6, p-value < 2.2e-16
## alternative hypothesis: true difference in means between group Stayed and group Left is not equal to 0
## 95 percent confidence interval:
##  -0.5394767 -0.4534706
## sample estimates:
## mean in group Stayed   mean in group Left 
##             3.380032             3.876505

Technical Interpretation

Reject the Ho, p-value < 0.01, there is a difference in means in time spent at the company

Non-Technical Interpretation

Employees who left had a difference of time spent at the compan

Graph

4. Last Evaluations vs Left

t-test

## 
##  Welch Two Sample t-test
## 
## data:  hr$last_evaluation by hr$left
## t = -0.72534, df = 5154.9, p-value = 0.4683
## alternative hypothesis: true difference in means between group Stayed and group Left is not equal to 0
## 95 percent confidence interval:
##  -0.009772224  0.004493874
## sample estimates:
## mean in group Stayed   mean in group Left 
##            0.7154734            0.7181126

Technical Interpretation

Retain the Ho, p-value > 0.01, there is no difference in means of last evaluation

Non-Technical Interpretation

Employees who left had no difference in last evaluations

Graph