Assignment 8
Jonathan Vicente & Jack Casmassima
2025-03-27
1. t-test of Average Monthly Hours by Left
t-test
Technical Interpretation
We reject the Ho, P-value < 0.01, where the average monthyl hours for employees that left is greater
Non-Technical Interpretation
Employees that work more hours are more likely to leave
Graph
2. t-test of satisfaction level by Left
t-test
##
## Welch Two Sample t-test
##
## data: hr$satisfaction_level by hr$left
## t = 46.636, df = 5167, 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:
## 0.2171815 0.2362417
## sample estimates:
## mean in group Stayed mean in group Left
## 0.6668096 0.4400980Technical Interpretation
We reject the Ho, P-value < 0.01, where the satisfaction level for employees that left is lower
Non-Technical Interpretation
Employees that are less satisfied are more likely to leave
Graph
3. t-test of promotions in the last 5 years by Left
t-test
##
## Welch Two Sample t-test
##
## data: hr$promotion_last_5years by hr$left
## t = 10.853, df = 13132, 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:
## 0.01715037 0.02471098
## sample estimates:
## mean in group Stayed mean in group Left
## 0.026251313 0.005320638Technical Interpretation
We reject the Ho, P-value < 0.01, where the number of promotions
in the last 5 years
for employees that left is higher
Non-Technical Interpretation
Employees that did not receive a promotion in the last 5 years Are more likely to leave
Graph
4. t-test of time spent at the company by 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 3.876505Technical Interpretation
We reject the Ho, P-value < 0.01, where the time spent at the company for employees that left is lower
Non-Technical Interpretation
Employees who spent less time at the company
are more likely to leave.
Graph
