HR_​Hypothesis_​Testing

Part 2:

Null hypothesis: monthly income = $6200

Alternative hypothesis: monthly income /= $6200

Sample mean: $5502.76

p-value for 2-tail test: 0

Based on sig level 0.05 and p-value rule, reject/fail to reject hypothesis?: fail to reject hypothesis

Conclusion: The average monthly income does not equal $6200; instead, it is significantly lower.

Part 3:

Sample proportion of attrition (mean of Attrition_Numeric): 0.171

Null hypothesis: attrition p <=12

Alternate hypothesis: attrition p > 12

Calculated one-tail p-value: 0

Based on significance level of 0.05, reject/fail to reject null hypothesis? Statistical evidence for HR director to be worried?: Reject null hypothesis. The mean, at over 17%, is well over the 12%, which should be a cause for concern for HR.

Part 4:

Null hypothesis: No relation between department and attrition rate.

Alternative hypothesis: There is a relation between department and attrition rate.

Department with highest raw count of "yes" for attrition: research and development

Chi-Square test stat: 6951.55

df: 2

p-value: 0

With a 0.05 significance level, reject/fail to reject null hypothesis? What does this mean?: Reject null hypothesis. There is a significant correlation between attrition and department, which means that the departments with highest attrition should be looked into.