1. You work for a firm that has invested heavily in an advertising campaign to increase sales at its stores this year, and you are tasked with evaluating whether to continue the campaign. In previous years, sales growth has averaged 5% per year across its 42 stores, with a standard deviation of 1.8%. This year, sales increased by 5.5% on average in those 42 stores.

Your manager wants to continue the campaign only if it was effective in increasing sales growth. Would you recommend continuing the campaign (use 95% confidence and a p-value test

reject it at that level.]

Here is the grading scheme for Hypothesis Test questions, each worth 9 points (it's easiest if you actually number the steps to make it obvious):

1. State the null and alternative hypotheses: 2 points - 1 for each
2. State the significance level you will use: 1 point
3. State the test statistic (z- or t-statistic) and the reason for using it: 1 point
   • Note: You will lose a full point if you don't state why you opted for z or t
4. Compute the value of the test statistic: 2 points
5. Find the critical value for the test statistic or calculate the p-value of the test statistic: 1 point
6. Decide whether to reject the null (and state why, mathematically, you do or don't), and interpret the result: 2 points - 1 for the decision and 1 for the interpretation