Exam 10: Data Mining

Exhibit 10.2 The following questions are based on the problem description and the output below. A college admissions officer wants to evaluate graduate school applicants based on their GMAT scores, verbal and quantitative. Students are classified as either successful (Group 1), marginally successful (Group 2) or not-successful (Group 3) in their graduate studies. The officer has data on 20 current students, 7 successful (Group 1), 6 marginally successful (Group 2) and 7 not successful (Group 3). ​ ​ ​ ​ -Refer to Exhibit 10.2. What is the quantitative test score value of the group centroid for group 1?

Exhibit 10.5 The information below is used for the following questions. A counselor wants to classify people as belonging to one of three groups based on two scores. The counselor has collected data on twenty people who are known to be in one of the three groups. The data for the problem are in the following spreadsheet. Relevant output is also included. ​ ​ ​ ​ ​ -Refer to Exhibit 10.5. What formulas should go in cells C24:D26 of the spreadsheet?

If using the regression tool for two-group discriminant analysis, in the regression dialog box, the Input X-Range entry corresponds to

Exhibit 10.6 The information below is used for the following questions. An investor wants to classify companies as being either a good investment, Group 1, or a poor investment, Group 2. He has gathered Liquidity, Profitability and Activity data on 18 companies he has invested in and run a regression analysis. Discriminant Analysis output has also been generated. The data for the problem and the relevant output are shown below. ​ ​ ​ ​ ​ ​ -Refer to Exhibit 10.6. Compute the discriminant score and predicted group for a company with Liquidity = 0.91, Profitability = 0.32 and Activity = 1.39.

Suppose the Fisher classification scores for an observation have been converted to the following probabilities: (i) 0.6 for Group 1 and (ii) 0.4 for Group 2. The observation will be classified to