[SAS Program]              
               
data rawres;
input gpa greq grev mat ar;
title 'Using Raw Residuals';
cards;
3.2 625 540 65 2.7
4.1 575 680 75 4.5
3.0 520 480 65 2.5
2.6 545 520 55 3.1
3.7 520 490 75 3.6
4.0 655 535 65 4.3
4.3 630 720 75 4.6
2.7 500 500 75 3.0
3.6 605 575 65 4.7
4.1 555 690 75 3.4
2.7 505 545 55 3.7
2.9 540 515 55 2.6
2.5 520 520 55 3.1
3.0 585 710 65 2.7
3.3 600 610 85 5.0
3.2 625 540 65 2.7
4.1 575 680 75 4.5
3.0 520 480 65 2.5
2.6 545 520 55 3.1
3.7 520 490 75 3.6
4.0 655 535 65 4.3
4.3 630 720 75 4.6
2.7 500 500 75 3.0
3.6 605 575 65 4.7
4.1 555 690 75 3.4
2.7 505 545 55 3.7
2.9 540 515 55 2.6
2.5 520 520 55 3.1
3.0 585 710 65 2.7
3.3 600 610 85 5.0
;
proc reg;
  model greq = grev / stb;
  output out=resid1 residual=rgreq;
proc reg data=resid1;
  model gpa = grev / stb;
  output out=resid2 residual=resgpa;
proc reg simple corr data=resid2;
  model gpa = rgreq / stb;
  model resgpa = rgreq / stb;
  model gpa = grev greq / stb;
run;

[SAS Output]
Using Raw Residuals                        08:45 Wednesday, February 3, 1999   1

Model: MODEL1
Dependent Variable: GREQ

Analysis of Variance

                         Sum of         Mean
Source          DF      Squares       Square      F Value       Prob>F
Model            1  15017.37802  15017.37802        7.855       0.0091
Error           28  53529.28864   1911.76031
C Total         29  68546.66667

    Root MSE      43.72368     R-square       0.2191
    Dep Mean     565.33333     Adj R-sq       0.1912
    C.V.           7.73414

Parameter Estimates

                 Parameter      Standard    T for H0:
Variable  DF      Estimate         Error   Parameter=0    Prob > |T|
INTERCEP   1    407.659543   56.82088827         7.174        0.0001
GREV       1      0.274056    0.09778216         2.803        0.0091

              Standardized
Variable  DF      Estimate
INTERCEP   1    0.00000000
GREV       1    0.46806254



Model: MODEL1  Dependent Variable: GPA

Analysis of Variance

                         Sum of         Mean
Source          DF      Squares       Square      F Value       Prob>F
Model            1      3.52782      3.52782       14.302       0.0008
Error           28      6.90685      0.24667
C Total         29     10.43467

    Root MSE       0.49666     R-square       0.3381
    Dep Mean       3.31333     Adj R-sq       0.3144
    C.V.          14.98980

Parameter Estimates

                 Parameter      Standard    T for H0:
Variable  DF      Estimate         Error   Parameter=0    Prob > |T|
INTERCEP   1      0.896672    0.64543448         1.389        0.1757
GREV       1      0.004200    0.00111072         3.782        0.0008

              Standardized
Variable  DF      Estimate
INTERCEP   1    0.00000000
GREV       1    0.58145214



Descriptive Statistics

Variables                Sum               Mean     Uncorrected SS
RGREQ                      0                  0       53529.288644     
GPA                     99.4       3.3133333333             339.78
RESGPA          -3.55271E-15       -1.18424E-16       6.9068458256    
GREV                   17260       575.33333333           10130200
GREQ                   16960       565.33333333            9656600


Variables           Variance      Std Deviation
RGREQ           1845.8375394       42.963211466    
GPA              0.359816092       0.5998467237
RESGPA          0.2381670974       0.4880236648    
GREV            6894.7126437       83.034406385
GREQ            2363.6781609       48.617673339


Correlation

CORR      RGREQ       GPA    RESGPA     GREV      GREQ
RGREQ    1.0000    0.3836    0.4715   0.0000    0.8837
GPA      0.3836    1.0000    0.8136   0.5815    0.6111
RESGPA   0.4715    0.8136    1.0000   0.0000    0.4167
GREV     0.0000    0.5815    0.0000   1.0000    0.4681
GREQ     0.8837    0.6111    0.4167   0.4681    1.0000



Model: MODEL1  Dependent Variable: GPA

Analysis of Variance

                         Sum of         Mean
Source          DF      Squares       Square      F Value       Prob>F
Model            1      1.53551      1.53551        4.831       0.0364
Error           28      8.89916      0.31783
C Total         29     10.43467

    Root MSE       0.56376     R-square       0.1472
    Dep Mean       3.31333     Adj R-sq       0.1167
    C.V.          17.01494

Parameter Estimates

                 Parameter      Standard    T for H0:
Variable  DF      Estimate         Error   Parameter=0    Prob > |T|
INTERCEP   1      3.313333    0.10292832        32.191        0.0001
RGREQ      1      0.005356    0.00243669         2.198        0.0364

              Standardized  Variable
Variable  DF      Estimate     Label
INTERCEP   1    0.00000000  Intercept
RGREQ      1    0.38360683  Residual



Model: MODEL2  Dependent Variable: RESGPA     Residual

Analysis of Variance

                         Sum of         Mean
Source          DF      Squares       Square      F Value       Prob>F
Model            1      1.53551      1.53551        8.004       0.0085
Error           28      5.37134      0.19183
C Total         29      6.90685

    Root MSE       0.43799     R-square       0.2223
    Dep Mean      -0.00000     Adj R-sq       0.1945
    C.V.      -3.698481E17

Parameter Estimates

                 Parameter      Standard    T for H0:
Variable  DF      Estimate         Error   Parameter=0    Prob > |T|
INTERCEP   1  -1.18424E-16    0.07996533        -0.000        1.0000
RGREQ      1      0.005356    0.00189307         2.829        0.0085

              Standardized  Variable
Variable  DF      Estimate     Label
INTERCEP   1    0.00000000  Intercept
RGREQ      1    0.47150439  Residual


Model: MODEL3  Dependent Variable: GPA

Analysis of Variance

                         Sum of         Mean
Source          DF      Squares       Square      F Value       Prob>F
Model            2      5.06333      2.53166       12.726       0.0001
Error           27      5.37134      0.19894
C Total         29     10.43467

    Root MSE       0.44603     R-square       0.4852
    Dep Mean       3.31333     Adj R-sq       0.4471
    C.V.          13.46153

Parameter Estimates

                 Parameter      Standard    T for H0:
Variable  DF      Estimate         Error   Parameter=0    Prob > |T|
INTERCEP   1     -1.286698    0.97652072        -1.318        0.1987
GREV       1      0.002733    0.00112876         2.421        0.0225
GREQ       1      0.005356    0.00192781         2.778        0.0098

              Standardized  Variable
Variable  DF      Estimate     Label
INTERCEP   1    0.00000000  Intercept
GREV       1    0.37826900
GREQ       1    0.43409398