Inferential Stats Project

Format your report so that it looks professional. Try to look at your report from the eyes of an outsider. You might want to ask someone around you for an impartial and honest opinion because that is how I will look at your work. You might even insist that they be brutally honest in their critique – it will help you in the long run. 1. [9 pts] An executive at the First National Bank is concerned that the bank is losing customers because mortgage applications are taking too long to be processed. The national average, according to an industry newsletter, is 6.5 business days. If the executive determines that the bank is taking longer than the national average then she will make major changes, including demoting or firing the manager of the mortgage department, even though he has an excellent work history with the bank. The bank executive has hired you to investigate the situation. You will conduct a hypothesis test to answer the bank executive’s questions so you collect a random sample of 108 recent mortgage applications. You record the time to process each application (number of business days). The data are located in your Excel file. a) Should your alternative be left-sided, right-sided, or two-sided? Explain. b) State your null and alternative hypotheses using correct symbols and notation. c) What would a Type I error be in this situation and who would be harmed by it? Be specific – jobs and money are on the line here! d) What would a Type II error be in this situation and who would be harmed by it? Be specific – jobs and money are on the line here! e) Conduct a one-sample t- test for the mean. Include your SPSS output or show your Excel calculations. f) State the P-value and give the conclusion in context using a significance level of 0.05. g) Based on the results of the hypothesis test, what decision should the bank executive make? Make sure to state this in a way that can be understood by someone who doesn’t know any statistics. h) Construct a 95% confidence interval for the mean mortgage processing time. Express the confidence interval in the form: “The average processing time for mortgages is ?? days. This survey is accurate to within ±?? days, ?? times out of ??”. Refer to your Chapter 16 Notes (Week 8) or Week 8 discussion for how to convert a confidence level into a “?? times out of ??” statement. Include your SPSS output or show your Excel calculations in your Word document