HRHypothesis_​Testing

Part 1

Part 2

(H0) Monthly Income = $6,200

(Ha) Alternative: Monthly Income does not = $6,200

Q2.1: What is the sample mean of the Monthly Income for our cleaned dataset?

$5,099

Q2.2: What is the p-value for this two-tail test?

0

Q2.3: Based on a significance level of 0.05 and the p-value rule from Chapter 8, do you reject or fail to reject the null hypothesis? Write a one-sentence conclusion for the CEO.

Reject the (H0) - "Monthly income is significantly different from the national average."

Part 3

H(0) Attrition portion is not significantly greater than 0.12.

H(A) Attrition portion is significantly greater than 0.12.

Q3.1: What is the sample proportion of attrition (the Mean of Attrition Numeric)?

0.17

Q3.2: What is the calculated one-tail p-value?

0

Q3.3: Based on a significance level of 0.05, do you reject or fail to reject the null hypothesis? Is there statistical evidence for the HR director to be worried?

We reject the null hypothesis. The HR director does need to be worried that rate of attrition is too high.

Part 4

H(0) - Department and Attrition are not related to each other.

H(A) - Department and Attrition are related to each other.

Q4.1: Looking at the Crosstab view, which department had the highest raw count of “Yes” for Attrition?

Research and Development

Q4.2: Look at the Statistics output. What is the Chi-Square test statistic, the degrees of freedom (df), and the exact p-value?

Chi Square: 10.974

df: 2

p-value: 0.064

Q4.3: Using a 0.05 significance level, do you reject or fail to reject the null hypothesis? What does this mean in plain English regarding Departments and Attrition?

Reject the Null Hypothesis. Department and Attrition are related to each other.