1. Left vs. Work Accident

a. Chi-Square Test

## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## | Chi-square contribution |
## |           N / Row Total |
## |           N / Col Total |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  14999 
## 
##  
##              | hr$Work_accident 
##      hr$left |         0 |         1 | Row Total | 
## -------------|-----------|-----------|-----------|
##            0 |      9428 |      2000 |     11428 | 
##              |    12.346 |    73.029 |           | 
##              |     0.825 |     0.175 |     0.762 | 
##              |     0.735 |     0.922 |           | 
##              |     0.629 |     0.133 |           | 
## -------------|-----------|-----------|-----------|
##            1 |      3402 |       169 |      3571 | 
##              |    39.510 |   233.709 |           | 
##              |     0.953 |     0.047 |     0.238 | 
##              |     0.265 |     0.078 |           | 
##              |     0.227 |     0.011 |           | 
## -------------|-----------|-----------|-----------|
## Column Total |     12830 |      2169 |     14999 | 
##              |     0.855 |     0.145 |           | 
## -------------|-----------|-----------|-----------|
## 
##  
## Statistics for All Table Factors
## 
## 
## Pearson's Chi-squared test 
## ------------------------------------------------------------
## Chi^2 =  358.5938     d.f. =  1     p =  5.698673e-80 
## 
## Pearson's Chi-squared test with Yates' continuity correction 
## ------------------------------------------------------------
## Chi^2 =  357.5624     d.f. =  1     p =  9.55824e-80 
## 
## 

b. Technical Interpretation

There is an association between leaving and work accidents, where employees without accidents are more likely to leave

c. Non-Technical Interpretation

Employees without work accidents are more than 3 times more likely to leave (0.265 / 0.078)

d. Graph

2. Left vs. Promotion in Last 5 Years

a. Chi-Square Test

## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## | Chi-square contribution |
## |           N / Row Total |
## |           N / Col Total |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  14999 
## 
##  
##              | hr$promotion_last_5years 
##      hr$left |         0 |         1 | Row Total | 
## -------------|-----------|-----------|-----------|
##            0 |     11128 |       300 |     11428 | 
##              |     0.290 |    13.343 |           | 
##              |     0.974 |     0.026 |     0.762 | 
##              |     0.758 |     0.940 |           | 
##              |     0.742 |     0.020 |           | 
## -------------|-----------|-----------|-----------|
##            1 |      3552 |        19 |      3571 | 
##              |     0.928 |    42.702 |           | 
##              |     0.995 |     0.005 |     0.238 | 
##              |     0.242 |     0.060 |           | 
##              |     0.237 |     0.001 |           | 
## -------------|-----------|-----------|-----------|
## Column Total |     14680 |       319 |     14999 | 
##              |     0.979 |     0.021 |           | 
## -------------|-----------|-----------|-----------|
## 
##  
## Statistics for All Table Factors
## 
## 
## Pearson's Chi-squared test 
## ------------------------------------------------------------
## Chi^2 =  57.26273     d.f. =  1     p =  3.813123e-14 
## 
## Pearson's Chi-squared test with Yates' continuity correction 
## ------------------------------------------------------------
## Chi^2 =  56.26163     d.f. =  1     p =  6.344155e-14 
## 
## 

b. Technical Interpretation

There is a statistically significant association between leaving the company and having received a promotion in the last 5 years (p < 0.001). Employees who were not promoted are significantly more likely to leave.

c. Non-Technical Interpretation

Employees who did not receive a promotion in the last 5 years are about 4 times more likely to leave (0.24 / 0.06).

d. Graph

3. Left vs. Department

a. Chi-Square Test

## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## | Chi-square contribution |
## |           N / Row Total |
## |           N / Col Total |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  14999 
## 
##  
##              | hr$Department 
##      hr$left |  accounting |          hr |          IT |  management |   marketing | product_mng |       RandD |       sales |     support |   technical |   Row Total | 
## -------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|
##            0 |         563 |         524 |         954 |         539 |         655 |         704 |         666 |        3126 |        1674 |        2023 |       11428 | 
##              |       0.783 |       2.709 |       0.391 |       7.250 |       0.002 |       0.408 |       7.346 |       0.255 |       0.348 |       1.178 |             | 
##              |       0.049 |       0.046 |       0.083 |       0.047 |       0.057 |       0.062 |       0.058 |       0.274 |       0.146 |       0.177 |       0.762 | 
##              |       0.734 |       0.709 |       0.778 |       0.856 |       0.763 |       0.780 |       0.846 |       0.755 |       0.751 |       0.744 |             | 
##              |       0.038 |       0.035 |       0.064 |       0.036 |       0.044 |       0.047 |       0.044 |       0.208 |       0.112 |       0.135 |             | 
## -------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|
##            1 |         204 |         215 |         273 |          91 |         203 |         198 |         121 |        1014 |         555 |         697 |        3571 | 
##              |       2.506 |       8.670 |       1.252 |      23.202 |       0.008 |       1.307 |      23.510 |       0.815 |       1.114 |       3.771 |             | 
##              |       0.057 |       0.060 |       0.076 |       0.025 |       0.057 |       0.055 |       0.034 |       0.284 |       0.155 |       0.195 |       0.238 | 
##              |       0.266 |       0.291 |       0.222 |       0.144 |       0.237 |       0.220 |       0.154 |       0.245 |       0.249 |       0.256 |             | 
##              |       0.014 |       0.014 |       0.018 |       0.006 |       0.014 |       0.013 |       0.008 |       0.068 |       0.037 |       0.046 |             | 
## -------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|
## Column Total |         767 |         739 |        1227 |         630 |         858 |         902 |         787 |        4140 |        2229 |        2720 |       14999 | 
##              |       0.051 |       0.049 |       0.082 |       0.042 |       0.057 |       0.060 |       0.052 |       0.276 |       0.149 |       0.181 |             | 
## -------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|-------------|
## 
##  
## Statistics for All Table Factors
## 
## 
## Pearson's Chi-squared test 
## ------------------------------------------------------------
## Chi^2 =  86.82547     d.f. =  9     p =  7.04213e-15 
## 
## 
## 

b. Technical Interpretation

There is a statistically significant relationship between department and employee turnover. The likelihood of an employee leaving varies depending on their department (p < 0.05).

c. Non-Technical Interpretation

Employees in sales and technical roles have a higher chance of leaving than those in management or support departments.

d. Graph

4. Left vs. Salary Level

a. Chi-Square Test

## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## | Chi-square contribution |
## |           N / Row Total |
## |           N / Col Total |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  14999 
## 
##  
##              | hr$salary 
##      hr$left |      high |       low |    medium | Row Total | 
## -------------|-----------|-----------|-----------|-----------|
##            0 |      1155 |      5144 |      5129 |     11428 | 
##              |    47.915 |    33.200 |     9.648 |           | 
##              |     0.101 |     0.450 |     0.449 |     0.762 | 
##              |     0.934 |     0.703 |     0.796 |           | 
##              |     0.077 |     0.343 |     0.342 |           | 
## -------------|-----------|-----------|-----------|-----------|
##            1 |        82 |      2172 |      1317 |      3571 | 
##              |   153.339 |   106.247 |    30.876 |           | 
##              |     0.023 |     0.608 |     0.369 |     0.238 | 
##              |     0.066 |     0.297 |     0.204 |           | 
##              |     0.005 |     0.145 |     0.088 |           | 
## -------------|-----------|-----------|-----------|-----------|
## Column Total |      1237 |      7316 |      6446 |     14999 | 
##              |     0.082 |     0.488 |     0.430 |           | 
## -------------|-----------|-----------|-----------|-----------|
## 
##  
## Statistics for All Table Factors
## 
## 
## Pearson's Chi-squared test 
## ------------------------------------------------------------
## Chi^2 =  381.225     d.f. =  2     p =  1.652087e-83 
## 
## 
## 

b. Technical Interpretation

The chi-square test shows a statistically significant relationship between salary level and employee attrition (p < 0.05). Employees with lower salaries are significantly more likely to leave.

c. Non-Technical Interpretation

Employees with low salaries are nearly 4 times more likely to leave than those with high salaries (0.37 vs. 0.09).

d. Graph