Answer Happy

Consider the classification trees in Figures 5.11(a) and (b). a. Use the mortgage default tree in Figure 5.11(a) to estimate the percentage of all mortgage applicants with a household income of $65,000 and debt of $20,000 who would default. Percentage of default applicants % b. Salford Systems (see Salford-systems.com) describes a study it helped carry out at UC San Diego to predict the probability that a heart attack survivor would have a second heart attack within 30 days. The study measured the values of over 100 variables concerning demographics, medical history, and lab results for heart attack survivors. From Salford Systems' description of the results, we have constructed the second heart attack tree in Figure 5.11(b). Use the tree to estimate the percentage of all 65-year-old heart attack survivors with a systolic blood pressure of 120 and with no sinus tachycardia who would have a second heart attack within 30 days. Salford Systems reports that the second heart attack tree has helped doctors tremendously in developing successful treatment plans for heart attack survivors. Percentage of heart attack survivors %
FIGURE 5.11 Classification Trees, Regression Trees, and Data for Exercises 5.2 and 5.3 (a) Mortgage default tree (b) Second heart attack tree No 0.10 0 0 1 1 1 1 0 0 0 0 0 1 1 1 0 1 0 0 1 0 1 1 0 0 1 0 0 0 1 1 1 Household income > $50,000? No On job >5 yr? (c) The coupon redemption data os CoupRedemp Coupon Purchases Card 0 10.52 0 14.89 15.75 29.27 48.15 51.40 29.89 21.23 17.55 46.61 28.01 15.97 50.10 51.62 27.48 4.95 -0--0000 43.25 35.04 28.94 53.67 13.24 51.54 42.05 29.71 39.24 58.38 23.75 23.89 50.94 36.37 34.40 38.01 55.87 21.46 40.75 46.52 34.93 31.97 42.28 26.28 0.05 0 1 1 1 0 1 0 1 0 0 0 1 0 1 0 1 1 1 1 0 1 1 0 0 1 0 0 0 1 1 1 1 0 1 1 0 OO Yes No 0 0 0 Yes Debt >$15,000? 0.01 Count Purchases>=36.37 Yes G^2 LogWorth 20 20.016097 16007719 Level Rate Prob Count 0 0.2000 0.2167 1 0.8000 0.7833 0.04 Card(1) G^2 Count 12 0 Level Rate Prob Count 0 0.0000 0.0397 1 1.0000 0.9603 0 12 4 16 Systolic Blood Pressure <91? Yes .70 (d) JMP output of a classification tree for the coupon redemption data (for Exercise 5.3) 0 RSquare 1 N 0.644 40 Count All Rows Purchases<36.37 Yes G^2 LogWorth 40 55.051105 5.5715641 Level Rate Prob Count 0.5500 0.5500 0.4500 0.4500 .02 Count G^2 8 11.090355 Level Rate Prob Count 0 0.5000 0.5019 1 0.5000 0.4981 4 4 Number of Splits 3 22 18 Age <62.5? No .50 Yes Sinus Tachycardia? Purchases>=42.28 Card(0) Count G^2 LogWorth 20 13.003319 0.9797146 Level Rate Prob Count 0 0.9000 0.8833 18 0.1000 0.1167 2 1 No Count G^2 5 6.7301167 Level Rate Prob Count 0 0.6000 0.5972 1 0.4000 0.4028 3 2 0 1 No Purchases<42.28 .11 Count 15 G^2 0 Level Rate Prob Prob Count 1.0000 0.9740 15 0 0.0000 0.0260