Assignment 8
Wyatt Jarboe and John O’Kane
2025-03-27
1. t-test of Average Monthly Hours by 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 207.4192Technical Interpretation
We reject the Ho, p-value < 0.01, where the average monthly 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 Last Evaluation by 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 0.7181126Technical Interpretation
We fail to reject the Ho, p-value >0.01, where there is no statistically significant difference
Non-Technical Interpretation
There is no meaningful difference in performance evaluation scores between those who stayed and those who left
Graph
3. t-test of Satisfaction Level by Left
t.test
##
## 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 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 levels are lower for those who left
Non-Technical Interpretation
Employees with lower satisfaction levels are more likely to leave
Graph
4. t.test of Time Spent at Company and Salary
t.test
##
## Welch Two Sample t-test
##
## data: time_spend_company by salary
## t = 4.3694, df = 1423, p-value = 1.336e-05
## alternative hypothesis: true difference in means between group high and group low is not equal to 0
## 95 percent confidence interval:
## 0.1402920 0.3688831
## sample estimates:
## mean in group high mean in group low
## 3.692805 3.438218Technical Interpretation
We reject the Ho, p-value<0.01, where the employees with higher salaries stay longer
Non-Technical Interpretation
Employees with a higher salary tend to stay at the company for longer
Graph
