Case Study: Mortgage Approval Time Study
Read the following case study:
A major financial services company wishes to better understand its mortgage approval process. In particular, the company is interested in learning about the effects of good versus fair credit history, the size of the mortgage (less than $500,000 versus greater than $500,000), and the region of the United States (western versus eastern) on the time it takes to get a mortgage approved. The database of mortgages approved in the last year is accessed, and a random sample of five approved mortgages is chosen for each of the eight combinations of the three variables. The data are shown in the table.
Mortgage Approval Time Study
Credit History Mortgage Size Region Approval Times (days) Approval Times (days) Approval Times (days) Approval Times (days) Approval Times (days)
Good <$500,000 Western 59 50 64 62 47
Fair <$500,000 Western 81 58 69 65 74 Good >$500,000 Western 38 52 58 60 65
Fair >$500,000 Western 146 159 133 143 129
Good <$500,000 Eastern 28 26 38 41 21
Fair <$500,000 Eastern 42 53 40 50 64 Good >$500,000 Eastern 49 31 49 42 38
Fair >$500,000 Eastern 106 115 126 118 138
First, conduct an analysis using the following steps:
Use the data shown in the table to conduct a design of experiment (DOE) in Microsoft Excel to determine the nature and magnitude of the effects of the three variables on mortgage approval times. Identify the key drivers of this process.
Determine the graphical display tool (Interaction Effects Chart, Scatter Chart, et cetera) that you would use to present the results of the DOE you conducted in Question 1. Provide a rationale for your response.
Assess the data sampling method:
Determine if the sample size is sufficient.
Identify circumstances under which would it have been appropriate to select a larger sample. Determine whether a sample of five mortgages is adequate to access the relative magnitudes of the effects of the variables.
Recommend a sample size for future study and discuss what analysis can be made with a larger sample size. (Hint: Look back at Chapters 2, 3, 5, and 6 for discussion of sampling.)
Provide other variable responses that might be of interest to measure and study. (Hint: If you were getting a mortgage or a loan, what are the two most important measures of the process you would have to go through?)
Propose one overall recommendation to the financial services company based on the DOE that could help reduce mortgage approval times.