Title 'Model Building using Forward Selection'.
Data list fixed records=1
/1 gpa 1-3 greq 5-7 grev 9-11 mat 13-14 ar 16-18.
begin data
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
end data.
Regression variables=gpa,greq,grev,mat,ar
/descriptives=mean,stddev,corr,n
/statistics=r,anova,cha,ci,coeff,tol,history
/dependent= gpa
/method=forward.
OUTPUT:
22 Dec 99 Model Building using Forward Selection Page 2
14:06:52 UCLA OAC IBM RS6000 AIX 3.2.5/4.
* * * * M U L T I P L E R E G R E S S I O N * * * *
Listwise Deletion of Missing Data
Mean Std Dev Label
GPA 3.313 .600
GREQ 565.333 48.618
GREV 575.333 83.034
MAT 67.000 9.248
AR 3.567 .838
N of Cases = 30
Correlation:
GPA GREQ GREV MAT AR
GPA 1.000 .611 .581 .604 .621
GREQ .611 1.000 .468 .267 .508
GREV .581 .468 1.000 .426 .405
MAT .604 .267 .426 1.000 .525
AR .621 .508 .405 .525 1.000
22 Dec 99 Model Building using Forward Selection Page 3
14:06:52 UCLA OAC IBM RS6000 AIX 3.2.5/4.
* * * * M U L T I P L E R E G R E S S I O N * * * *
Equation Number 1 Dependent Variable.. GPA
Descriptive Statistics are printed on Page 2
Block Number 1. Method: Forward Criterion PIN .0500
Variable(s) Entered on Step Number 1.. AR
Multiple R .62072 Analysis of Variance
R Square .38529 R Square Change .38529 DF Sum of Squares Mean Square
Adjusted R Square .36334 F Change 17.55023 Regression 1 4.02041 4.02041
Standard Error .47862 Signif F Change .0003 Residual 28 6.41425 .22908
F = 17.55023 Signif F = .0003
------------------------------------------ Variables in the Equation ------------------------------------------
Variable B SE B 95% Confdnce Intrvl B Beta Tolerance VIF T Sig T
AR .444081 .106004 .226942 .661220 .620721 1.000000 1.000 4.189 .0003
(Constant) 1.729444 .388047 .934566 2.524322 4.457 .0001
----------- not in ------------
Variable Tolerance VIF
GREQ .742099 1.348
GREV .835714 1.197
MAT .724599 1.380
22 Dec 99 Model Building using Forward Selection Page 4
14:06:52 UCLA OAC IBM RS6000 AIX 3.2.5/4.
* * * * M U L T I P L E R E G R E S S I O N * * * *
Equation Number 1 Dependent Variable.. GPA
Variable(s) Entered on Step Number 2.. GREV
Multiple R .71798 Analysis of Variance
R Square .51549 R Square Change .13020 DF Sum of Squares Mean Square
Adjusted R Square .47960 F Change 7.25547 Regression 2 5.37898 2.68949
Standard Error .43272 Signif F Change .0120 Residual 27 5.05568 .18725
F = 14.36329 Signif F = .0001
------------------------------------------ Variables in the Equation ------------------------------------------
Variable B SE B 95% Confdnce Intrvl B Beta Tolerance VIF T Sig T
GREV .002851 .001059 6.79359E-04 .005023 .394705 .835714 1.197 2.694 .0120
AR .329625 .104835 .114521 .544729 .460738 .835714 1.197 3.144 .0040
(Constant) .497178 .576516 -.685734 1.680090 .862 .3961
----------- not in ------------
Variable Tolerance VIF
GREQ .659821 1.516
MAT .670304 1.492
End Block Number 1 PIN = .050 Limits reached.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Summary table
-------------
Step MultR Rsq AdjRsq F(Eqn) SigF RsqCh FCh SigCh Variable BetaIn Correl
1 .6207 .3853 .3633 17.550 .000 .3853 17.550 .000 In: AR .6207 .6207
2 .7180 .5155 .4796 14.363 .000 .1302 7.255 .012 In: GREV .3947 .5815
22 Dec 99 Model Building using Forward Selection Page 5
14:06:52 UCLA OAC IBM RS6000 AIX 3.2.5/4.
Preceding task required .14 seconds CPU time; .15 seconds elapsed.
41 0
40 command lines read.
0 errors detected.
0 warnings issued.
0 seconds CPU time.
0 seconds elapsed time.
End of job.