MATH 533 Project B and C

Part B: Hypothesis Testing and Confidence Intervals

Complete the following four hypotheses, using ? = 0.05 for each.

1. Mean sales per week exceeds 41.5 per salesperson
2. Proportion receiving online training is less than 55%
3. Mean calls made among those with no training is less than 145
4. Mean time per call is greater than 15 minutes
   1. Using the same data set from part A, perform the hypothesis test for each speculation in order to see if there is evidence to support the manager's belief. Use the Seven Elements of a Test of Hypothesis from Section 7.1 of your text book, as well as the p-value calculation from Section 7.3, and explain your conclusion in simple terms.
   2. Compute 99% confidence intervals for each of the variables described in a.-d., and interpret these intervals.
   3. Write a report about the results, distilling down the results in a way that would be understandable to someone who does not know statistics. Clear explanations and interpretations are critical.
   4. All DeVry University policies are in effect, including the plagiarism policy.
   5. Project Part B report is due by the end of Week 6.
   6. Project Part B is worth 100 total points. See grading rubric below.

Format for report:

1. Summary Report (about one paragraph on each of the speculations a.- d.)
2. Appendix with the calculations of the Seven Elements of a Test of Hypothesis, the p-values, and the confidence intervals. Include the Excel formulas used in the calculations.

Part B: Grading Rubric

Part C: Regression and Correlation Analysis

Use the dependent variable (labeled Y) and oneof the independent variables (labeled X1, X2, and X3) in the data file. Select and use one independent variable throughout this analysis. Use Excel to perform the regression and correlation analysis to answer the following.

1. Generate a scatterplot for the specified dependent variable (Y) and the selected independent variable (X), including the graph of the "best fit" line. Interpret.
2. Determine the equation of the "best fit" line, which describes the relationship between the dependent variable and the selected independent variable.
3. Determine the coefficient of correlation. Interpret.
4. Determine the coefficient of determination. Interpret.
5. Test the utility of this regression model, represented by a hypothesis test of b=0 using ?=0.10. Interpret results, including the p-value.
6. Based on the findings in steps 1-5, analyze the ability of the independent variable to predict the dependent variable?
7. Compute the confidence interval for b, using a 95% confidence level. Interpret this interval.
8. Compute the 99% confidence interval for the dependent variable, for a selected value of the independent variable. Each student can choose a value to use for the independent variable (use same value in the next step). Interpret this interval.
9. Using the same chosen value for part (8), estimate the 99% prediction interval for the dependent variable. Interpret this interval.
10. What can be said about the value of the dependent variable for values of the independent variable that are outside the range of the sample values? Explain.
11. All DeVry University policies are in effect, including the plagiarism policy.
12. Project Part C report is due by the end of Week 7.
13. Project Part C is worth 100 total points. See grading rubric below.

Summarize your results from Steps 1–10 in a 3-page report. The report should explain and interpret the results in ways that are understandable to someone who does not know statistics.

Submission: The summary report and all of the work done in 1–10 (Excel output and interpretations) as an appendix

Format for report:

1. Summary Report
2. Steps 1-10 addressed with appropriate output, graphs and interpretations. Be sure to number each step 1-10.