Salary is hypothesized to depend on educational qualification and occupation. To understand the dependency, the salaries of 40 individuals [SalaryData.csv] are collected and each person’s educational qualification and occupation are noted. Educational qualification is at three levels, High school graduate, Bachelor, and Doctorate. Occupation is at four levels, Administrative and clerical, Sales, Professional or speciality, and Executive or managerial. A different number of observations are in each level of education – occupation combination. [Assume that the data follows a normal distribution. In reality, the normality assumption may not always hold if the sample size is small.]
What is the interaction between the two treatments? Analyze the effects of one variable on the other (Education and Occupation) with the help of an interaction plot.[hint: use the ‘pointplot’ function from the ‘seaborn’ function].
Perform a two-way ANOVA based on Salary with respect to both Education and Occupation (along with their interaction Education*Occupation). State the null and alternative hypotheses and state your results. How will you interpret this result?
Explain the business implications of performing ANOVA for this particular case study.
| Education | Occupation | Salary |
| Doctorate | Adm-clerical | 153197 |
| Doctorate | Adm-clerical | 115945 |
| Doctorate | Adm-clerical | 175935 |
| Doctorate | Adm-clerical | 220754 |
| Doctorate | Sales | 170769 |
| Doctorate | Sales | 219420 |
| Doctorate | Sales | 237920 |
| Doctorate | Sales | 160540 |
| Doctorate | Sales | 180934 |
| Doctorate | Prof-specialty | 248156 |
| Doctorate | Prof-specialty | 247724 |
| Doctorate | Prof-specialty | 249207 |
| Doctorate | Prof-specialty | 235334 |
| Doctorate | Prof-specialty | 248871 |
| Doctorate | Prof-specialty | 257345 |
| Bachelors | Adm-clerical | 160910 |
| Bachelors | Adm-clerical | 162494 |
| Bachelors | Adm-clerical | 188729 |
| Bachelors | Prof-specialty | 99185 |
| Bachelors | Prof-specialty | 90135 |
| Bachelors | Prof-specialty | 100135 |
| Bachelors | Prof-specialty | 133696 |
| Bachelors | Sales | 149909 |
| Bachelors | Sales | 191712 |
| Bachelors | Sales | 167431 |
| Bachelors | Sales | 260151 |
| HS-grad | Sales | 50103 |
| HS-grad | Sales | 50122 |
| HS-grad | Sales | 52242 |
| HS-grad | Adm-clerical | 75333 |
| HS-grad | Adm-clerical | 77743 |
| HS-grad | Adm-clerical | 83203 |
| HS-grad | Prof-specialty | 90456 |
| HS-grad | Prof-specialty | 100678 |
| HS-grad | Prof-specialty | 95469 |
| Bachelors | Exec-managerial | 173935 |
| Bachelors | Exec-managerial | 212448 |
| Bachelors | Exec-managerial | 173664 |
| Bachelors | Exec-managerial | 212760 |
| Doctorate | Exec-managerial | 212781 |