Multiple Least-Square Regression Example 1 Dependent Variable, Y: CEMENT MIX X1, X2, X3, X4 are four ingredients in mix Obs Y X1 X2 X3 X4 X1X2 X1X3 X1X4 1 78.5 7 26 6 60 182 42 420 2 74.3 1 29 15 52 29 15 52 3 104.3 11 56 8 47 616 88 517 4 87.6 11 31 8 47 341 88 517 5 95.9 7 52 6 33 364 42 231 6 109.2 11 55 9 22 605 99 242 7 102.7 3 71 17 6 213 51 18 8 72.5 1 31 22 44 31 22 44 9 93.1 2 54 18 22 108 36 44 10 115.9 21 47 4 26 987 84 546 11 83.8 1 40 23 34 40 23 34 12 113.3 11 66 9 12 726 99 132 13 109.4 10 68 8 12 680 80 120 14 . 10 70 6 14 700 60 140 15 . 15 75 4 12 1125 60 180 Multiple Least-Square Regression Example 2 General linear model & related residual plots The GLM Procedure Number of Observations Read 15 Number of Observations Used 13 Multiple Least-Square Regression Example 3 General linear model & related residual plots The GLM Procedure Dependent Variable: Y Sum of Source DF Squares Mean Square F Value Pr > F Model 4 2670.365050 667.591263 117.64 <.0001 Error 8 45.398026 5.674753 Corrected Total 12 2715.763077 R-Square Coeff Var Root MSE Y Mean 0.983284 2.496434 2.382174 95.42308 Source DF Type I SS Mean Square F Value Pr > F X1 1 1450.076328 1450.076328 255.53 <.0001 X2 1 1207.782266 1207.782266 212.83 <.0001 X3 1 9.793869 9.793869 1.73 0.2254 X4 1 2.712588 2.712588 0.48 0.5089 Source DF Type III SS Mean Square F Value Pr > F X1 1 281.3174755 281.3174755 49.57 0.0001 X2 1 163.2592552 163.2592552 28.77 0.0007 X3 1 3.1459775 3.1459775 0.55 0.4778 X4 1 2.7125876 2.7125876 0.48 0.5089 Standard Parameter Estimate Error t Value Pr > |t| Intercept 55.28234314 11.01724868 5.02 0.0010 X1 1.62976040 0.23147223 7.04 0.0001 X2 0.58798438 0.10962267 5.36 0.0007 X3 0.16734770 0.22475814 0.74 0.4778 X4 -0.07179770 0.10384657 -0.69 0.5089 Multiple Least-Square Regression Example 4 General linear model & related residual plots The GLM Procedure Observation Observed Predicted Residual 1 78.50000000 78.67448398 -0.17448398 2 74.30000000 72.74038564 1.55961436 3 104.30000000 104.10112263 0.19887737 4 87.60000000 89.40151301 -1.80151301 5 95.90000000 95.90061594 -0.00061594 6 109.20000000 105.47542849 3.72457151 7 102.70000000 104.33264028 -1.63264028 8 72.50000000 75.66216990 -3.16216990 9 93.10000000 91.72572981 1.37427019 10 115.90000000 115.94522809 -0.04522809 11 83.80000000 81.83935408 1.96064592 12 113.30000000 112.66123374 0.63876626 13 109.40000000 112.04009442 -2.64009442 14 * . 112.73777239 . 15 * . 123.63539631 . 95% Confidence Limits for Observation Mean Predicted Value 1 74.94837105 82.40059691 2 69.75726883 75.72350246 3 98.63416098 109.56808428 4 86.62444420 92.17858182 5 92.66902393 99.13220794 6 103.43385896 107.51699802 7 100.97222811 107.69305245 8 72.24829215 79.07604766 9 89.28384995 94.16760966 10 111.31872937 120.57172681 11 78.44902289 85.22968528 12 110.12969158 115.19277590 13 109.27047786 114.80971097 14 * 109.51433239 115.96121239 15 * 120.01610747 127.25468514 * Observation was not used in this analysis Sum of Residuals -0.0000000 Sum of Squared Residuals 45.3980265 Sum of Squared Residuals - Error SS -0.0000000 PRESS Statistic 521.1471688 First Order Autocorrelation -0.1359120 Durbin-Watson D 2.1176203 Multiple Least-Square Regression Example 5 General linear model & related residual plots Plot of Y*YHAT. Symbol used is 'P'. Plot of RESID*YHAT. Symbol used is 'R'. Y | | 120 + | P | P | P P | | P 100 + | P | P | | P | P 80 + P | | P P | | | 60 + | | | | | 40 + | | | | | 20 + | | | | | R R 0 + R R R R R R R | R R R | | | | -20 + | --+-----------+-----------+-----------+-----------+-----------+-----------+- 70 80 90 100 110 120 130 YHAT NOTE: 4 obs had missing values. 2 obs hidden. Forward Regression 6 The REG Procedure Model: MODEL1 Dependent Variable: Y Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Forward Selection: Step 1 Variable X1X2 Entered: R-Square = 0.7884 and C(p) = 61.2741 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 1 2141.20142 2141.20142 40.99 <.0001 Error 11 574.56165 52.23288 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 79.34871 3.21263 31864 610.04 <.0001 X1X2 0.04246 0.00663 2141.20142 40.99 <.0001 Bounds on condition number: 1, 1 -------------------------------------------------------------------------------- Forward Selection: Step 2 Variable X2 Entered: R-Square = 0.9677 and C(p) = 3.7308 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 2 2628.02762 1314.01381 149.77 <.0001 Error 10 87.73545 8.77355 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 60.98339 2.79502 4176.65198 476.05 <.0001 X2 0.47545 0.06383 486.82620 55.49 <.0001 X1X2 0.03049 0.00316 818.60089 93.30 <.0001 Forward Regression 7 The REG Procedure Model: MODEL1 Dependent Variable: Y Forward Selection: Step 2 Bounds on condition number: 1.3492, 5.397 -------------------------------------------------------------------------------- Forward Selection: Step 3 Variable X1 Entered: R-Square = 0.9790 and C(p) = 1.9915 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 3 2658.60032 886.20011 139.53 <.0001 Error 9 57.16276 6.35142 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 53.70675 4.08112 1099.93944 173.18 <.0001 X1 1.27458 0.58095 30.57270 4.81 0.0559 X2 0.63581 0.09106 309.66576 48.76 <.0001 X1X2 0.00420 0.01228 0.74172 0.12 0.7404 Bounds on condition number: 28.215, 162.22 -------------------------------------------------------------------------------- Forward Selection: Step 4 Variable X4 Entered: R-Square = 0.9826 and C(p) = 2.7694 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 4 2668.59260 667.14815 113.15 <.0001 Error 8 47.17048 5.89631 Corrected Total 12 2715.76308 Forward Regression 8 The REG Procedure Model: MODEL1 Dependent Variable: Y Forward Selection: Step 4 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 63.33232 8.37464 337.20901 57.19 <.0001 X1 1.21827 0.56142 27.76487 4.71 0.0618 X2 0.51063 0.13017 90.73245 15.39 0.0044 X4 -0.11727 0.09008 9.99228 1.69 0.2292 X1X2 0.00574 0.01189 1.37353 0.23 0.6423 Bounds on condition number: 28.498, 255.42 -------------------------------------------------------------------------------- No other variable met the 0.5000 significance level for entry into the model. Summary of Forward Selection Variable Number Partial Model Step Entered Vars In R-Square R-Square C(p) F Value Pr > F 1 X1X2 1 0.7884 0.7884 61.2741 40.99 <.0001 2 X2 2 0.1793 0.9677 3.7308 55.49 <.0001 3 X1 3 0.0113 0.9790 1.9915 4.81 0.0559 4 X4 4 0.0037 0.9826 2.7694 1.69 0.2292 Backward Regression 9 The REG Procedure Model: MODEL1 Dependent Variable: Y Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Backward Elimination: Step 0 All Variables Entered: R-Square = 0.9849 and C(p) = 8.0000 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 7 2674.88306 382.12615 46.74 0.0003 Error 5 40.88001 8.17600 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 2.89001 88.10760 0.00880 0.00 0.9751 X1 5.71832 6.95186 5.53192 0.68 0.4482 X2 1.18331 1.03510 10.68509 1.31 0.3047 X3 0.39744 0.47725 5.67012 0.69 0.4429 X4 0.55666 1.02214 2.42494 0.30 0.6094 X1X2 -0.05315 0.09235 2.70798 0.33 0.5899 X1X3 0.05274 0.08404 3.22026 0.39 0.5578 X1X4 -0.05635 0.08923 3.26127 0.40 0.5554 Bounds on condition number: 2454.4, 35266 -------------------------------------------------------------------------------- Backward Elimination: Step 1 Variable X4 Removed: R-Square = 0.9841 and C(p) = 6.2966 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 6 2672.45812 445.40969 61.71 <.0001 Error 6 43.30495 7.21749 Corrected Total 12 2715.76308 Backward Regression 10 The REG Procedure Model: MODEL1 Dependent Variable: Y Backward Elimination: Step 1 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 50.73167 6.36354 458.71950 63.56 0.0002 X1 1.96787 0.89299 35.04961 4.86 0.0697 X2 0.62280 0.10352 261.21478 36.19 0.0010 X3 0.17604 0.23487 4.05439 0.56 0.4819 X1X2 -0.00368 0.01565 0.39898 0.06 0.8219 X1X3 0.01972 0.05468 0.93910 0.13 0.7307 X1X4 -0.00815 0.01053 4.31668 0.60 0.4687 Bounds on condition number: 45.877, 641.33 -------------------------------------------------------------------------------- Backward Elimination: Step 2 Variable X1X2 Removed: R-Square = 0.9839 and C(p) = 4.3454 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 5 2672.05915 534.41183 85.60 <.0001 Error 7 43.70393 6.24342 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 51.21222 5.60497 521.22187 83.48 <.0001 X1 1.77343 0.31331 200.02920 32.04 0.0008 X2 0.60850 0.07792 380.71800 60.98 0.0001 X3 0.18419 0.21606 4.53733 0.73 0.4221 X1X3 0.01750 0.05009 0.76201 0.12 0.7371 X1X4 -0.00680 0.00823 4.26633 0.68 0.4357 Bounds on condition number: 6.5286, 116.17 -------------------------------------------------------------------------------- Backward Elimination: Step 3 Variable X1X3 Removed: R-Square = 0.9836 and C(p) = 2.4386 Backward Regression 11 The REG Procedure Model: MODEL1 Dependent Variable: Y Backward Elimination: Step 3 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 4 2671.29713 667.82428 120.15 <.0001 Error 8 44.46594 5.55824 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 50.94043 5.23729 525.83473 94.60 <.0001 X1 1.82417 0.26194 269.56531 48.50 0.0001 X2 0.62373 0.06094 582.27711 104.76 <.0001 X3 0.18721 0.20369 4.69521 0.84 0.3849 X1X4 -0.00609 0.00752 3.64467 0.66 0.4415 Bounds on condition number: 5.1557, 63.591 -------------------------------------------------------------------------------- Backward Elimination: Step 4 Variable X1X4 Removed: R-Square = 0.9823 and C(p) = 0.8844 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 3 2667.65246 889.21749 166.34 <.0001 Error 9 48.11061 5.34562 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 48.19363 3.91330 810.75653 151.67 <.0001 X1 1.69589 0.20458 367.33211 68.72 <.0001 X2 0.65691 0.04423 1178.96145 220.55 <.0001 X3 0.25002 0.18471 9.79387 1.83 0.2089 Bounds on condition number: 3.2511, 22.37 -------------------------------------------------------------------------------- Backward Elimination: Step 5 Backward Regression 12 The REG Procedure Model: MODEL1 Dependent Variable: Y Backward Elimination: Step 5 Variable X3 Removed: R-Square = 0.9787 and C(p) = 0.0822 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 2 2657.85859 1328.92930 229.50 <.0001 Error 10 57.90448 5.79045 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 52.57735 2.28617 3062.60416 528.91 <.0001 X1 1.46831 0.12130 848.43186 146.52 <.0001 X2 0.66225 0.04585 1207.78227 208.58 <.0001 Bounds on condition number: 1.0551, 4.2205 -------------------------------------------------------------------------------- All variables left in the model are significant at the 0.1000 level. Summary of Backward Elimination Variable Number Partial Model Step Removed Vars In R-Square R-Square C(p) F Value Pr > F 1 X4 6 0.0009 0.9841 6.2966 0.30 0.6094 2 X1X2 5 0.0001 0.9839 4.3454 0.06 0.8219 3 X1X3 4 0.0003 0.9836 2.4386 0.12 0.7371 4 X1X4 3 0.0013 0.9823 0.8844 0.66 0.4415 5 X3 2 0.0036 0.9787 0.0822 1.83 0.2089 Stepwise Regression 13 The REG Procedure Model: MODEL1 Dependent Variable: Y Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Stepwise Selection: Step 1 Variable X1X2 Entered: R-Square = 0.7884 and C(p) = 61.2741 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 1 2141.20142 2141.20142 40.99 <.0001 Error 11 574.56165 52.23288 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 79.34871 3.21263 31864 610.04 <.0001 X1X2 0.04246 0.00663 2141.20142 40.99 <.0001 Bounds on condition number: 1, 1 -------------------------------------------------------------------------------- Stepwise Selection: Step 2 Variable X2 Entered: R-Square = 0.9677 and C(p) = 3.7308 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 2 2628.02762 1314.01381 149.77 <.0001 Error 10 87.73545 8.77355 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 60.98339 2.79502 4176.65198 476.05 <.0001 X2 0.47545 0.06383 486.82620 55.49 <.0001 X1X2 0.03049 0.00316 818.60089 93.30 <.0001 Stepwise Regression 14 The REG Procedure Model: MODEL1 Dependent Variable: Y Stepwise Selection: Step 2 Bounds on condition number: 1.3492, 5.397 -------------------------------------------------------------------------------- Stepwise Selection: Step 3 Variable X1 Entered: R-Square = 0.9790 and C(p) = 1.9915 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 3 2658.60032 886.20011 139.53 <.0001 Error 9 57.16276 6.35142 Corrected Total 12 2715.76308 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 53.70675 4.08112 1099.93944 173.18 <.0001 X1 1.27458 0.58095 30.57270 4.81 0.0559 X2 0.63581 0.09106 309.66576 48.76 <.0001 X1X2 0.00420 0.01228 0.74172 0.12 0.7404 Bounds on condition number: 28.215, 162.22 -------------------------------------------------------------------------------- Stepwise Selection: Step 4 Variable X1X2 Removed: R-Square = 0.9787 and C(p) = 0.0822 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 2 2657.85859 1328.92930 229.50 <.0001 Error 10 57.90448 5.79045 Corrected Total 12 2715.76308 Stepwise Regression 15 The REG Procedure Model: MODEL1 Dependent Variable: Y Stepwise Selection: Step 4 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F Intercept 52.57735 2.28617 3062.60416 528.91 <.0001 X1 1.46831 0.12130 848.43186 146.52 <.0001 X2 0.66225 0.04585 1207.78227 208.58 <.0001 Bounds on condition number: 1.0551, 4.2205 -------------------------------------------------------------------------------- All variables left in the model are significant at the 0.1500 level. No other variable met the 0.1500 significance level for entry into the model. Summary of Stepwise Selection Variable Variable Number Partial Model Step Entered Removed Vars In R-Square R-Square C(p) F Value Pr > F 1 X1X2 1 0.7884 0.7884 61.2741 40.99 <.0001 2 X2 2 0.1793 0.9677 3.7308 55.49 <.0001 3 X1 3 0.0113 0.9790 1.9915 4.81 0.0559 4 X1X2 2 0.0003 0.9787 0.0822 0.12 0.7404 R-square Regression 16 The REG Procedure Model: MODEL1 Dependent Variable: Y R-Square Selection Method Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Number in Model R-Square Variables in Model 1 0.7884 X1X2 1 0.6663 X2 1 0.6570 X1X3 1 0.5339 X1 1 0.5296 X4 1 0.2859 X3 1 0.0674 X1X4 ---------------------------------------------------- 2 0.9787 X1 X2 2 0.9677 X2 X1X2 2 0.9491 X4 X1X2 2 0.9157 X1 X4 2 0.9045 X4 X1X4 2 0.8870 X2 X1X3 2 0.8775 X2 X1X4 2 0.8707 X4 X1X3 2 0.8649 X1 X1X2 2 0.8634 X1X2 X1X4 2 0.8553 X3 X4 2 0.8470 X2 X3 2 0.8249 X3 X1X2 2 0.7961 X1X2 X1X3 2 0.7668 X1 X1X4 2 0.7132 X1X3 X1X4 2 0.6699 X1 X1X3 2 0.6663 X2 X4 2 0.6574 X3 X1X3 2 0.5482 X1 X3 2 0.3374 X3 X1X4 ---------------------------------------------------- 3 0.9823 X1 X2 X3 3 0.9821 X1 X2 X4 3 0.9819 X1 X2 X1X4 3 0.9790 X1 X2 X1X2 3 0.9787 X1 X2 X1X3 3 0.9724 X2 X4 X1X2 3 0.9691 X2 X1X2 X1X4 3 0.9690 X2 X1X2 X1X3 3 0.9679 X2 X3 X1X2 3 0.9607 X4 X1X2 X1X4 3 0.9545 X4 X1X2 X1X3 3 0.9517 X3 X4 X1X2 3 0.9492 X1 X4 X1X2 R-square Regression 17 The REG Procedure Model: MODEL1 Dependent Variable: Y R-Square Selection Method Number in Model R-Square Variables in Model 3 0.9381 X2 X4 X1X4 3 0.9306 X1 X4 X1X3 3 0.9238 X1 X4 X1X4 3 0.9232 X1 X3 X4 3 0.9209 X4 X1X3 X1X4 3 0.9200 X3 X4 X1X4 3 0.9113 X3 X4 X1X3 3 0.9069 X2 X1X3 X1X4 3 0.9044 X2 X3 X1X3 3 0.8950 X2 X4 X1X3 3 0.8851 X1X2 X1X3 X1X4 3 0.8844 X2 X3 X1X4 3 0.8797 X2 X3 X4 3 0.8774 X1 X1X2 X1X3 3 0.8694 X1 X1X2 X1X4 3 0.8674 X1 X3 X1X2 3 0.8639 X3 X1X2 X1X4 3 0.8429 X1 X1X3 X1X4 3 0.8364 X3 X1X2 X1X3 3 0.7692 X1 X3 X1X4 3 0.7403 X3 X1X3 X1X4 3 0.6841 X1 X3 X1X3 ---------------------------------------------------- 4 0.9836 X1 X2 X3 X1X4 4 0.9833 X1 X2 X3 X4 4 0.9827 X2 X4 X1X2 X1X4 4 0.9826 X1 X2 X4 X1X2 4 0.9824 X1 X2 X4 X1X4 4 0.9824 X1 X2 X3 X1X2 4 0.9823 X1 X2 X3 X1X3 4 0.9823 X1 X2 X4 X1X3 4 0.9822 X1 X2 X1X3 X1X4 4 0.9821 X1 X2 X1X2 X1X4 4 0.9806 X1 X4 X1X2 X1X4 4 0.9790 X1 X2 X1X2 X1X3 4 0.9746 X2 X4 X1X2 X1X3 4 0.9728 X2 X3 X4 X1X2 4 0.9707 X2 X3 X1X2 X1X4 4 0.9696 X2 X1X2 X1X3 X1X4 4 0.9695 X2 X3 X1X2 X1X3 4 0.9616 X4 X1X2 X1X3 X1X4 4 0.9609 X3 X4 X1X2 X1X4 4 0.9561 X3 X4 X1X2 X1X3 4 0.9550 X1 X4 X1X2 X1X3 4 0.9522 X1 X3 X4 X1X2 4 0.9459 X2 X4 X1X3 X1X4 4 0.9448 X2 X3 X4 X1X4 4 0.9352 X1 X3 X4 X1X3 4 0.9334 X1 X4 X1X3 X1X4 R-square Regression 18 The REG Procedure Model: MODEL1 Dependent Variable: Y R-Square Selection Method Number in Model R-Square Variables in Model 4 0.9310 X3 X4 X1X3 X1X4 4 0.9294 X1 X3 X4 X1X4 4 0.9262 X2 X3 X4 X1X3 4 0.9103 X2 X3 X1X3 X1X4 4 0.8875 X1 X1X2 X1X3 X1X4 4 0.8854 X3 X1X2 X1X3 X1X4 4 0.8807 X1 X3 X1X2 X1X3 4 0.8700 X1 X3 X1X2 X1X4 4 0.8437 X1 X3 X1X3 X1X4 ---------------------------------------------------- 5 0.9839 X1 X2 X3 X1X3 X1X4 5 0.9837 X1 X2 X3 X1X2 X1X4 5 0.9837 X1 X2 X3 X4 X1X4 5 0.9836 X1 X2 X3 X4 X1X2 5 0.9834 X1 X2 X3 X4 X1X3 5 0.9829 X2 X3 X4 X1X2 X1X4 5 0.9828 X1 X2 X4 X1X2 X1X3 5 0.9828 X1 X2 X4 X1X2 X1X4 5 0.9827 X1 X2 X4 X1X3 X1X4 5 0.9827 X2 X4 X1X2 X1X3 X1X4 5 0.9826 X1 X2 X1X2 X1X3 X1X4 5 0.9825 X1 X2 X3 X1X2 X1X3 5 0.9809 X1 X3 X4 X1X2 X1X4 5 0.9808 X1 X4 X1X2 X1X3 X1X4 5 0.9748 X2 X3 X4 X1X2 X1X3 5 0.9711 X2 X3 X1X2 X1X3 X1X4 5 0.9618 X3 X4 X1X2 X1X3 X1X4 5 0.9571 X1 X3 X4 X1X2 X1X3 5 0.9506 X2 X3 X4 X1X3 X1X4 5 0.9374 X1 X3 X4 X1X3 X1X4 5 0.8879 X1 X3 X1X2 X1X3 X1X4 ---------------------------------------------------- 6 0.9841 X1 X2 X3 X1X2 X1X3 X1X4 6 0.9839 X1 X2 X3 X4 X1X3 X1X4 6 0.9838 X1 X2 X3 X4 X1X2 X1X4 6 0.9837 X1 X2 X3 X4 X1X2 X1X3 6 0.9829 X2 X3 X4 X1X2 X1X3 X1X4 6 0.9829 X1 X2 X4 X1X2 X1X3 X1X4 6 0.9810 X1 X3 X4 X1X2 X1X3 X1X4 ---------------------------------------------------- 7 0.9849 X1 X2 X3 X4 X1X2 X1X3 X1X4 Adjusted R-square Regression 19 The REG Procedure Model: MODEL1 Dependent Variable: Y Adjusted R-Square Selection Method Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Number in Adjusted Model R-Square R-Square Variables in Model 3 0.9764 0.9823 X1 X2 X3 3 0.9762 0.9821 X1 X2 X4 3 0.9759 0.9819 X1 X2 X1X4 4 0.9754 0.9836 X1 X2 X3 X1X4 4 0.9749 0.9833 X1 X2 X3 X4 2 0.9744 0.9787 X1 X2 4 0.9740 0.9827 X2 X4 X1X2 X1X4 4 0.9739 0.9826 X1 X2 X4 X1X2 4 0.9736 0.9824 X1 X2 X4 X1X4 4 0.9736 0.9824 X1 X2 X3 X1X2 4 0.9735 0.9823 X1 X2 X3 X1X3 4 0.9735 0.9823 X1 X2 X4 X1X3 4 0.9734 0.9822 X1 X2 X1X3 X1X4 4 0.9732 0.9821 X1 X2 X1X2 X1X4 5 0.9724 0.9839 X1 X2 X3 X1X3 X1X4 5 0.9721 0.9837 X1 X2 X3 X1X2 X1X4 5 0.9720 0.9837 X1 X2 X3 X4 X1X4 3 0.9719 0.9790 X1 X2 X1X2 5 0.9718 0.9836 X1 X2 X3 X4 X1X2 5 0.9716 0.9834 X1 X2 X3 X4 X1X3 3 0.9716 0.9787 X1 X2 X1X3 4 0.9710 0.9806 X1 X4 X1X2 X1X4 5 0.9707 0.9829 X2 X3 X4 X1X2 X1X4 5 0.9706 0.9828 X1 X2 X4 X1X2 X1X3 5 0.9705 0.9828 X1 X2 X4 X1X2 X1X4 5 0.9704 0.9827 X1 X2 X4 X1X3 X1X4 5 0.9704 0.9827 X2 X4 X1X2 X1X3 X1X4 5 0.9701 0.9826 X1 X2 X1X2 X1X3 X1X4 5 0.9699 0.9825 X1 X2 X3 X1X2 X1X3 4 0.9684 0.9790 X1 X2 X1X2 X1X3 6 0.9681 0.9841 X1 X2 X3 X1X2 X1X3 X1X4 6 0.9679 0.9839 X1 X2 X3 X4 X1X3 X1X4 6 0.9675 0.9838 X1 X2 X3 X4 X1X2 X1X4 6 0.9675 0.9837 X1 X2 X3 X4 X1X2 X1X3 5 0.9672 0.9809 X1 X3 X4 X1X2 X1X4 5 0.9671 0.9808 X1 X4 X1X2 X1X3 X1X4 6 0.9658 0.9829 X2 X3 X4 X1X2 X1X3 X1X4 6 0.9657 0.9829 X1 X2 X4 X1X2 X1X3 X1X4 7 0.9639 0.9849 X1 X2 X3 X4 X1X2 X1X3 X1X4 3 0.9632 0.9724 X2 X4 X1X2 6 0.9620 0.9810 X1 X3 X4 X1X2 X1X3 X1X4 4 0.9618 0.9746 X2 X4 X1X2 X1X3 2 0.9612 0.9677 X2 X1X2 Adjusted R-square Regression 20 The REG Procedure Model: MODEL1 Dependent Variable: Y Adjusted R-Square Selection Method Number in Adjusted Model R-Square R-Square Variables in Model 4 0.9592 0.9728 X2 X3 X4 X1X2 3 0.9588 0.9691 X2 X1X2 X1X4 3 0.9587 0.9690 X2 X1X2 X1X3 3 0.9572 0.9679 X2 X3 X1X2 5 0.9568 0.9748 X2 X3 X4 X1X2 X1X3 4 0.9561 0.9707 X2 X3 X1X2 X1X4 4 0.9544 0.9696 X2 X1X2 X1X3 X1X4 4 0.9542 0.9695 X2 X3 X1X2 X1X3 5 0.9505 0.9711 X2 X3 X1X2 X1X3 X1X4 3 0.9475 0.9607 X4 X1X2 X1X4 4 0.9424 0.9616 X4 X1X2 X1X3 X1X4 4 0.9413 0.9609 X3 X4 X1X2 X1X4 3 0.9394 0.9545 X4 X1X2 X1X3 2 0.9389 0.9491 X4 X1X2 3 0.9355 0.9517 X3 X4 X1X2 5 0.9346 0.9618 X3 X4 X1X2 X1X3 X1X4 4 0.9342 0.9561 X3 X4 X1X2 X1X3 4 0.9325 0.9550 X1 X4 X1X2 X1X3 3 0.9323 0.9492 X1 X4 X1X2 4 0.9283 0.9522 X1 X3 X4 X1X2 5 0.9264 0.9571 X1 X3 X4 X1X2 X1X3 4 0.9188 0.9459 X2 X4 X1X3 X1X4 3 0.9174 0.9381 X2 X4 X1X4 4 0.9172 0.9448 X2 X3 X4 X1X4 5 0.9154 0.9506 X2 X3 X4 X1X3 X1X4 3 0.9074 0.9306 X1 X4 X1X3 4 0.9027 0.9352 X1 X3 X4 X1X3 4 0.9001 0.9334 X1 X4 X1X3 X1X4 2 0.8989 0.9157 X1 X4 3 0.8984 0.9238 X1 X4 X1X4 3 0.8976 0.9232 X1 X3 X4 4 0.8965 0.9310 X3 X4 X1X3 X1X4 3 0.8945 0.9209 X4 X1X3 X1X4 4 0.8941 0.9294 X1 X3 X4 X1X4 3 0.8934 0.9200 X3 X4 X1X4 5 0.8927 0.9374 X1 X3 X4 X1X3 X1X4 4 0.8894 0.9262 X2 X3 X4 X1X3 2 0.8853 0.9045 X4 X1X4 3 0.8817 0.9113 X3 X4 X1X3 3 0.8759 0.9069 X2 X1X3 X1X4 3 0.8725 0.9044 X2 X3 X1X3 4 0.8654 0.9103 X2 X3 X1X3 X1X4 2 0.8644 0.8870 X2 X1X3 3 0.8600 0.8950 X2 X4 X1X3 2 0.8531 0.8775 X2 X1X4 3 0.8468 0.8851 X1X2 X1X3 X1X4 3 0.8458 0.8844 X2 X3 X1X4 2 0.8449 0.8707 X4 X1X3 3 0.8396 0.8797 X2 X3 X4 Adjusted R-square Regression 21 The REG Procedure Model: MODEL1 Dependent Variable: Y Adjusted R-Square Selection Method Number in Adjusted Model R-Square R-Square Variables in Model 2 0.8379 0.8649 X1 X1X2 3 0.8365 0.8774 X1 X1X2 X1X3 2 0.8360 0.8634 X1X2 X1X4 4 0.8312 0.8875 X1 X1X2 X1X3 X1X4 4 0.8281 0.8854 X3 X1X2 X1X3 X1X4 2 0.8264 0.8553 X3 X4 3 0.8258 0.8694 X1 X1X2 X1X4 3 0.8233 0.8674 X1 X3 X1X2 4 0.8210 0.8807 X1 X3 X1X2 X1X3 3 0.8186 0.8639 X3 X1X2 X1X4 2 0.8164 0.8470 X2 X3 5 0.8078 0.8879 X1 X3 X1X2 X1X3 X1X4 4 0.8051 0.8700 X1 X3 X1X2 X1X4 3 0.7905 0.8429 X1 X1X3 X1X4 2 0.7898 0.8249 X3 X1X2 3 0.7818 0.8364 X3 X1X2 X1X3 1 0.7692 0.7884 X1X2 4 0.7656 0.8437 X1 X3 X1X3 X1X4 2 0.7553 0.7961 X1X2 X1X3 2 0.7201 0.7668 X1 X1X4 3 0.6923 0.7692 X1 X3 X1X4 2 0.6559 0.7132 X1X3 X1X4 3 0.6537 0.7403 X3 X1X3 X1X4 1 0.6359 0.6663 X2 1 0.6259 0.6570 X1X3 2 0.6038 0.6699 X1 X1X3 2 0.5996 0.6663 X2 X4 2 0.5889 0.6574 X3 X1X3 3 0.5788 0.6841 X1 X3 X1X3 1 0.4916 0.5339 X1 1 0.4868 0.5296 X4 2 0.4578 0.5482 X1 X3 1 0.2210 0.2859 X3 2 0.2049 0.3374 X3 X1X4 1 -.0174 0.0674 X1X4 Mallows. Cp statistics Regression 22 The REG Procedure Model: MODEL1 Dependent Variable: Y C(p) Selection Method Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Number in Model C(p) R-Square Variables in Model 2 0.0822 0.9787 X1 X2 3 0.8844 0.9823 X1 X2 X3 3 0.9374 0.9821 X1 X2 X4 3 1.0129 0.9819 X1 X2 X1X4 3 1.9915 0.9790 X1 X2 X1X2 3 2.0779 0.9787 X1 X2 X1X3 4 2.4386 0.9836 X1 X2 X3 X1X4 4 2.5526 0.9833 X1 X2 X3 X4 4 2.7478 0.9827 X2 X4 X1X2 X1X4 4 2.7694 0.9826 X1 X2 X4 X1X2 4 2.8352 0.9824 X1 X2 X4 X1X4 4 2.8410 0.9824 X1 X2 X3 X1X2 4 2.8672 0.9823 X1 X2 X3 X1X3 4 2.8711 0.9823 X1 X2 X4 X1X3 4 2.9003 0.9822 X1 X2 X1X3 X1X4 4 2.9409 0.9821 X1 X2 X1X2 X1X4 4 3.4275 0.9806 X1 X4 X1X2 X1X4 2 3.7308 0.9677 X2 X1X2 4 3.9876 0.9790 X1 X2 X1X2 X1X3 3 4.1653 0.9724 X2 X4 X1X2 5 4.3454 0.9839 X1 X2 X3 X1X3 X1X4 5 4.4115 0.9837 X1 X2 X3 X1X2 X1X4 5 4.4231 0.9837 X1 X2 X3 X4 X1X4 5 4.4552 0.9836 X1 X2 X3 X4 X1X2 5 4.4986 0.9834 X1 X2 X3 X4 X1X3 5 4.6800 0.9829 X2 X3 X4 X1X2 X1X4 5 4.7013 0.9828 X1 X2 X4 X1X2 X1X3 5 4.7217 0.9828 X1 X2 X4 X1X2 X1X4 5 4.7316 0.9827 X1 X2 X4 X1X3 X1X4 5 4.7435 0.9827 X2 X4 X1X2 X1X3 X1X4 5 4.7925 0.9826 X1 X2 X1X2 X1X3 X1X4 5 4.8246 0.9825 X1 X2 X3 X1X2 X1X3 3 5.2655 0.9691 X2 X1X2 X1X4 3 5.2965 0.9690 X2 X1X2 X1X3 5 5.3582 0.9809 X1 X3 X4 X1X2 X1X4 5 5.3770 0.9808 X1 X4 X1X2 X1X3 X1X4 4 5.4498 0.9746 X2 X4 X1X2 X1X3 3 5.6542 0.9679 X2 X3 X1X2 4 6.0340 0.9728 X2 X3 X4 X1X2 6 6.2966 0.9841 X1 X2 X3 X1X2 X1X3 X1X4 6 6.3312 0.9839 X1 X2 X3 X4 X1X3 X1X4 6 6.3939 0.9838 X1 X2 X3 X4 X1X2 X1X4 6 6.3989 0.9837 X1 X2 X3 X4 X1X2 X1X3 Mallows. Cp statistics Regression 23 The REG Procedure Model: MODEL1 Dependent Variable: Y C(p) Selection Method Number in Model C(p) R-Square Variables in Model 6 6.6766 0.9829 X2 X3 X4 X1X2 X1X3 X1X4 6 6.6935 0.9829 X1 X2 X4 X1X2 X1X3 X1X4 4 6.7158 0.9707 X2 X3 X1X2 X1X4 4 7.0967 0.9696 X2 X1X2 X1X3 X1X4 4 7.1416 0.9695 X2 X3 X1X2 X1X3 6 7.3069 0.9810 X1 X3 X4 X1X2 X1X3 X1X4 5 7.3790 0.9748 X2 X3 X4 X1X2 X1X3 7 8.0000 0.9849 X1 X2 X3 X4 X1X2 X1X3 X1X4 3 8.0704 0.9607 X4 X1X2 X1X4 5 8.5835 0.9711 X2 X3 X1X2 X1X3 X1X4 4 9.7541 0.9616 X4 X1X2 X1X3 X1X4 2 9.8988 0.9491 X4 X1X2 4 9.9879 0.9609 X3 X4 X1X2 X1X4 3 10.1005 0.9545 X4 X1X2 X1X3 3 11.0583 0.9517 X3 X4 X1X2 4 11.5737 0.9561 X3 X4 X1X2 X1X3 5 11.6746 0.9618 X3 X4 X1X2 X1X3 X1X4 3 11.8668 0.9492 X1 X4 X1X2 4 11.9555 0.9550 X1 X4 X1X2 X1X3 4 12.8843 0.9522 X1 X3 X4 X1X2 5 13.2583 0.9571 X1 X3 X4 X1X2 X1X3 4 14.9833 0.9459 X2 X4 X1X3 X1X4 4 15.3359 0.9448 X2 X3 X4 X1X4 5 15.4005 0.9506 X2 X3 X4 X1X3 X1X4 3 15.5731 0.9381 X2 X4 X1X4 3 18.0609 0.9306 X1 X4 X1X3 4 18.5357 0.9352 X1 X3 X4 X1X3 4 19.1239 0.9334 X1 X4 X1X3 X1X4 5 19.7923 0.9374 X1 X3 X4 X1X3 X1X4 4 19.9162 0.9310 X3 X4 X1X3 X1X4 3 20.3025 0.9238 X1 X4 X1X4 4 20.4424 0.9294 X1 X3 X4 X1X4 3 20.5207 0.9232 X1 X3 X4 2 20.9909 0.9157 X1 X4 3 21.2845 0.9209 X4 X1X3 X1X4 4 21.4970 0.9262 X2 X3 X4 X1X3 3 21.5581 0.9200 X3 X4 X1X4 3 24.4715 0.9113 X3 X4 X1X3 2 24.7370 0.9045 X4 X1X4 3 25.9259 0.9069 X2 X1X3 X1X4 3 26.7706 0.9044 X2 X3 X1X3 4 26.8108 0.9103 X2 X3 X1X3 X1X4 3 29.8851 0.8950 X2 X4 X1X3 2 30.5371 0.8870 X2 X1X3 3 33.1779 0.8851 X1X2 X1X3 X1X4 3 33.4089 0.8844 X2 X3 X1X4 2 33.6739 0.8775 X2 X1X4 4 34.3770 0.8875 X1 X1X2 X1X3 X1X4 3 34.9603 0.8797 X2 X3 X4 Mallows. Cp statistics Regression 24 The REG Procedure Model: MODEL1 Dependent Variable: Y C(p) Selection Method Number in Model C(p) R-Square Variables in Model 4 35.0728 0.8854 X3 X1X2 X1X3 X1X4 3 35.7390 0.8774 X1 X1X2 X1X3 2 35.9367 0.8707 X4 X1X3 5 36.2456 0.8879 X1 X3 X1X2 X1X3 X1X4 4 36.6364 0.8807 X1 X3 X1X2 X1X3 2 37.8665 0.8649 X1 X1X2 2 38.3831 0.8634 X1X2 X1X4 3 38.3963 0.8694 X1 X1X2 X1X4 3 39.0297 0.8674 X1 X3 X1X2 4 40.1691 0.8700 X1 X3 X1X2 X1X4 3 40.1992 0.8639 X3 X1X2 X1X4 2 41.0539 0.8553 X3 X4 2 43.8124 0.8470 X2 X3 3 47.1803 0.8429 X1 X1X3 X1X4 4 48.9107 0.8437 X1 X3 X1X3 X1X4 3 49.3578 0.8364 X3 X1X2 X1X3 2 51.1709 0.8249 X3 X1X2 2 60.7444 0.7961 X1X2 X1X3 1 61.2741 0.7884 X1X2 2 70.4766 0.7668 X1 X1X4 3 71.6564 0.7692 X1 X3 X1X4 3 81.2685 0.7403 X3 X1X3 X1X4 2 88.2488 0.7132 X1X3 X1X4 3 99.9179 0.6841 X1 X3 X1X3 1 101.8532 0.6663 X2 2 102.6611 0.6699 X1 X1X3 2 103.8384 0.6663 X2 X4 1 104.9217 0.6570 X1X3 2 106.7916 0.6574 X3 X1X3 2 143.0821 0.5482 X1 X3 1 145.8051 0.5339 X1 1 147.2482 0.5296 X4 2 213.0825 0.3374 X3 X1X4 1 228.2064 0.2859 X3 1 300.7848 0.0674 X1X4 Stepwise Regression with No Int. and other Optional Statistics 25 The REG Procedure Model: MODEL1 Dependent Variable: Y Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 Stepwise Selection: Step 1 Variable X2 Entered: R-Square = 0.9614 and C(p) = 675.0274 NOTE: No intercept in model. R-Square is redefined. Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 1 116413 116413 298.80 <.0001 Error 12 4675.14075 389.59506 Uncorrected Total 13 121088 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F X2 1.87679 0.10857 116413 298.80 <.0001 Bounds on condition number: 1, 1 -------------------------------------------------------------------------------- Stepwise Selection: Step 2 Variable X4 Entered: R-Square = 0.9895 and C(p) = 177.8678 NOTE: No intercept in model. R-Square is redefined. Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 2 119815 59907 517.47 <.0001 Error 11 1273.46733 115.76976 Uncorrected Total 13 121088 Stepwise Regression with No Int. and other Optional Statistics 26 The REG Procedure Model: MODEL1 Dependent Variable: Y Stepwise Selection: Step 2 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F X2 1.53355 0.08667 36242 313.05 <.0001 X4 0.65759 0.12131 3401.67341 29.38 0.0002 Bounds on condition number: 2.1446, 8.5786 -------------------------------------------------------------------------------- Stepwise Selection: Step 3 Variable X1 Entered: R-Square = 0.9962 and C(p) = 59.6483 NOTE: No intercept in model. R-Square is redefined. Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 3 120634 40211 885.33 <.0001 Error 10 454.19509 45.41951 Uncorrected Total 13 121088 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F X1 1.44826 0.34100 819.27225 18.04 0.0017 X2 1.35129 0.06920 17319 381.31 <.0001 X4 0.59354 0.07747 2666.31355 58.70 <.0001 Bounds on condition number: 3.4846, 25.889 -------------------------------------------------------------------------------- Stepwise Selection: Step 4 Variable X3 Entered: R-Square = 0.9984 and C(p) = 22.6279 NOTE: No intercept in model. R-Square is redefined. Stepwise Regression with No Int. and other Optional Statistics 27 The REG Procedure Model: MODEL1 Dependent Variable: Y Stepwise Selection: Step 4 Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 4 120900 30225 1444.80 <.0001 Error 9 188.27873 20.91986 Uncorrected Total 13 121088 Parameter Standard Variable Estimate Error Type II SS F Value Pr > F X1 2.36137 0.34518 979.01317 46.80 <.0001 X2 1.08834 0.08744 3241.02438 154.93 <.0001 X3 1.01494 0.28467 265.91636 12.71 0.0061 X4 0.41313 0.07297 670.58841 32.06 0.0003 Bounds on condition number: 12.079, 126.97 -------------------------------------------------------------------------------- All variables left in the model are significant at the 0.1500 level. No other variable met the 0.1500 significance level for entry into the model. NOTE: No intercept in model. R-Square is redefined. Summary of Stepwise Selection Variable Variable Number Partial Model Step Entered Removed Vars In R-Square R-Square C(p) F Value Pr > F 1 X2 1 0.9614 0.9614 675.027 298.80 <.0001 2 X4 2 0.0281 0.9895 177.868 29.38 0.0002 3 X1 3 0.0068 0.9962 59.6483 18.04 0.0017 4 X3 4 0.0022 0.9984 22.6279 12.71 0.0061 Stepwise Regression with No Int. and other Optional Statistics 28 The REG Procedure Model: MODEL1 Dependent Variable: Y Number of Observations Read 15 Number of Observations Used 13 Number of Observations with Missing Values 2 NOTE: No intercept in model. R-Square is redefined. Analysis of Variance Sum of Mean Source DF Squares Square F Value Pr > F Model 4 120900 30225 1444.80 <.0001 Error 9 188.27873 20.91986 Uncorrected Total 13 121088 Root MSE 4.57382 R-Square 0.9984 Dependent Mean 95.42308 Adj R-Sq 0.9978 Coeff Var 4.79320 Parameter Estimates Parameter Standard Variable DF Estimate Error t Value Pr > |t| Type I SS X1 1 2.36137 0.34518 6.84 <.0001 88359 X2 1 1.08834 0.08744 12.45 <.0001 29608 X3 1 1.01494 0.28467 3.57 0.0061 2261.64150 X4 1 0.41313 0.07297 5.66 0.0003 670.58841 Parameter Estimates Standardized Variable DF Type II SS Estimate 95% Confidence Limits X1 1 979.01317 0.22902 1.58051 3.14222 X2 1 3241.02438 0.56859 0.89054 1.28614 X3 1 265.91636 0.13967 0.37097 1.65892 X4 1 670.58841 0.15421 0.24807 0.57820 Covariance of Estimates Variable X1 X2 X3 X4 X1 0.1191509082 -0.025629347 0.0729084214 -0.015328061 X2 -0.025629347 0.0076454602 -0.020996144 0.0026420658 X3 0.0729084214 -0.020996144 0.0810396971 -0.014404936 X4 -0.015328061 0.0026420658 -0.014404936 0.0053245835 Stepwise Regression with No Int. and other Optional Statistics 29 The REG Procedure Model: MODEL1 Dependent Variable: Y Correlation of Estimates Variable X1 X2 X3 X4 X1 1.0000 -0.8492 0.7420 -0.6085 X2 -0.8492 1.0000 -0.8435 0.4141 X3 0.7420 -0.8435 1.0000 -0.6935 X4 -0.6085 0.4141 -0.6935 1.0000