Answer Happy

A Toyota dealer wished to predict the sales prices of used Toyota Corollas and gathered 1,436 observations concerning sales prices of used Corollas and the values of 36 predictor variables. Sixty percent of the observations (actually 862 observations) were randomly selected as the training data set, and the remaining 40 percent of the observations (574 observations) were used as the validation data set. A portion of the data, as well as part of a JMP regression tree analysis of the data, are shown in Figures 5.24 and 5.25. The default minimum split size of 5 was used. a. Using the information given in Figures 5.24 and 5.25, find the prediction of the sales price of used Toyota Corolla 1437, which has just been obtained by the Toyota dealer and has not yet been sold. Prediction of the sales price b-1. Redo the regression trees analysis and part a using a specified minimum split size of 20. Find the prediction of the sales price of used Toyota Corolla 1437, which has just been obtained by the Toyota dealer and has not yet been sold. Prediction of the sales price The prediction using a minimum split size of 20 is the default minimum split size of 5.
FIGURE 5.24 The JMP Output of a Portion of the Used Toyota Corolla Sales Price Data and of Part of a Regression Tree Analysis of These Data Model 1 TOYOTA Corolla 2.0 D4D HATCHB TERRA 2/3-Doors 2 TOYOTA Corolla 2.0 D4D HATCHB TERRA 2/3-Doors 3 TOYOTA Corolla 2.0 D4D HATCHB TERRA 2/3-Doors 8 TOYOTA Corolla 2.0 D4D 90 3DR TERRA 2/3-Doors 9 TOYOTA Corolla 1800 T SPORT VVTI 2/3-Doors 10 TOYOTA Corolla 1.9 D HATCHB TERRA 2/3-Doors 1437 TOYOTA Corolla 2.0 D4D 90 3DR TERRA 2/3-Doors 16900 13750 13950 18600 21500 12950 10 Blue 1437 Grey 1 2 3 8 9 10 1437 Color Automatic CC Doors Cylinders Gears Quarterly_Tax Weight Mfg Guarantee BOVAG Guarantee Guarantee_Perlod 1 Blue 210 1165 2 Silver 210 1165 3 Blue 210 1165 8 Grey 1245 1185 9 Red 1 2 3 8 9 10 1437 Training Validation 1437 1 1 1 1 1 1 1 1 1 1 1 1 1 0 2000 0 2000 0 2000 1 0 2000 0 1800 0 1900 0 2000 RSquare 1 1 1 3 3 3 3 3 3 3 0 0 0 0 1 0 0 1 1 1 1 0 1 1 0 0 0.933 938.52912 862 0.853 1387.5365 574 Price Age_08_04 Mfg_Month Mfg_Year KM Fuel Type HP Met Color 13500 1 1 1 1 0 0 1 0 0 0 4 5 4 5 4 5 4 5 4 5 4 5 4 5 ABS Airbag 1 Airbag 2 Airco Automatic_alrco Boardcomputer CD Player Central Lock Powered_Windows 1 0 1 1 0 T 1 1 1 1 0 0 0 0 0 0 0 1 RMSE N Number of Splits 47 0 0 0 Validation Price Residual Price Predicted Leaf Number 43 210 100 185 210 0 0 0 0 23 23 24 30 27 23 27 Power Steering Radio Mistlamps Sport Model Backseat Divider Metallic Rim Radio_cassette Tow_Bar Validation 0 O Validation 0 O Validation AICC 14349.9 1105 1245 1 1 10 10 9 3 6 10 6 1 1 2002 46986 2002 72937 2002 41711 2002 75889 2002 19700 2002 71138 2002 94612 1 1 1 1 0 1 1 0 1 1 0 0 1 1 0 0 0 0 0 1 0 0 1 0 1 0 0 0 Diesel 90 Diesel 90 Diesel 90 Diesel 90 Petrol 192 Diesel 69 Diesel 90 0 Leaf Label 1 1 0 1 1 0 1 0 0 1 1 0 0 1 1 1 0 0 3 3 3 3 3 3 3 1 0 0 1 1 0 1 0 Training 0 Training Training 0 0 Validation 0 Training Age_08_04<33&Weight=1125&Metallic Rim<1&Mfg_Year<2003&Doors<5
FIGURE 5.25 The First 10 Leafs and the Last 10 Leafs of the 48-Leaf Corolla Price Regression Tree Leaf Report Leaf Label Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM>=145996&ABS<1 Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM>=145996&ABS>=1&Fuel Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM>=145996&ABS>=1&Fuel Type(Diesel) Type(Petrol) Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM<145996&Quarterly_Tax<85&Mfg_Guarantee<1 Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM<145996&Quarterly_Tax<85&Mfg_Guarantee>=1&Doors<5 Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM<145996&Quarterly_Tax<85&Mfg_Guarantee>=1&Doors>=5 Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM<145996&Quarterly_Tax=85&Tow_Bar>=1 Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM<145996&Quarterly_Tax=85&Tow_Bar<&BOVAG_Guarantee<1 Age_08_04>=33&Age_08_04>=57&Age_08_04>=69&KM< 145996&Quarterly_Tax>=85&Tow_Bar<1&BOVAG_Guarantee>= 1 Age_08_04>=33&Age_08_04>=57&Age_08_04<69&KM>=135337&HP<110 ⠀ Age_08_04<33&Weight<1125&Age_08_04>=19&Central_Lock< 1 Age_08_04<33&Weight<1125&Age_08_04>=19&Central_Lock=1&Weight<1115 Age_08_04<33&Weight<1125&Age_08_04>=19&Central_Lock=1&Weight>=1115 Age_08_04<33&Weight<1125&Age_08_04<19 Age_08_04<33&Weight>=1125&Metallic_Rim<1&Mfg_Year<2003&Doors<5 Age_08_04<33&Weight>=1125&Metallic_Rim<1&Mfg_Year<2003&Doors>=5 Age_08_04<33&Weight>=1125&Metallic_Rim<1&Mfg_Year>=2003&Quarterly_Tax<234 Age_08_04<33&Weight>=1125&Metallic_Rim<1&Mfg_Year>=2003&Quarterly_Tax>=234 Age_08_04<33&Weight>=1125&Metallic_Rim>=1&Mfg_Month>=4 Age_08_04<33&Weight>=1125&Metallic_Rim>=1&Mfg_Month<4 Mean 5811.25 6200 7050 7687.84884 7993.71429 8840 8112.47368 7607 8720.51282 7166.77778 E 14390.8333 15989.5833 17504.375 18286.4 16270 17934.5385 19468.75 21810 21228.125 22982.2222