1. Satisfaction Level

## 
##  Welch Two Sample t-test
## 
## data:  satisfaction_level by left
## t = 46.636, df = 5167, p-value < 2.2e-16
## alternative hypothesis: true difference in means between group 0 and group 1 is not equal to 0
## 95 percent confidence interval:
##  0.2171815 0.2362417
## sample estimates:
## mean in group 0 mean in group 1 
##       0.6668096       0.4400980

A. P-Value Interpretation:

The p-value is very small, so the difference is statistically significant

B. Non-Technical Interpretation

Employees who left were less satisfied than those who stayed.

C. Box Plot:

2. Last Evaluation

## 
##  Welch Two Sample t-test
## 
## data:  last_evaluation by left
## t = -0.72534, df = 5154.9, p-value = 0.4683
## alternative hypothesis: true difference in means between group 0 and group 1 is not equal to 0
## 95 percent confidence interval:
##  -0.009772224  0.004493874
## sample estimates:
## mean in group 0 mean in group 1 
##       0.7154734       0.7181126

A. P-Value Interpretation

The p-value is very small, so the difference is statistically significant

B. Non-Technical Interpretation

Employees who left had different evaluation scores than those who stayed

C. Box Plot:

3. Number of Projects

## 
##  Welch Two Sample t-test
## 
## data:  number_project by left
## t = -2.1663, df = 4236.5, p-value = 0.03034
## alternative hypothesis: true difference in means between group 0 and group 1 is not equal to 0
## 95 percent confidence interval:
##  -0.131136535 -0.006540119
## sample estimates:
## mean in group 0 mean in group 1 
##        3.786664        3.855503

A. P-Value Interpretation

The p-value is very small, so the difference is statistically significant

B. Non-Technical Interpretation

Employees who left worked on a different number of projects than those who stayed.

C. Box Plot:

4. Average Monthly Hours

t.test(average_montly_hours ~ left, data = hr)
## 
##  Welch Two Sample t-test
## 
## data:  average_montly_hours by left
## t = -7.5323, df = 4875.1, p-value = 5.907e-14
## alternative hypothesis: true difference in means between group 0 and group 1 is not equal to 0
## 95 percent confidence interval:
##  -10.534631  -6.183384
## sample estimates:
## mean in group 0 mean in group 1 
##        199.0602        207.4192

A. P-Value Interpretation

The p-value is very small, so the difference is statistically significant

B. Non-Technical Interpretation

Employees who left worked different hours than those who stayed

C. Box Plot: