SPSS scripts and output for stepwise regression analysis
USE ALL.
COMPUTE filter_$=(AcademicYear=2006 and IsGrouped=0 and sector=1).
VARIABLE LABEL filter_$’AcademicYear=2006 and IsGrouped=0 and sector=1 (FILTER)’. VALUE LABELS filter_$ 0 ‘Not Selected’ 1 ‘Selected’.
FORMAT filter_$(f1.0). FILTER BY filter_$. EXECUTE . REGRESSION /MISSING LISTWISE
/STATISTICS COEFF OUTS R ANOVA /CRITERIA=PIN(.05) POUT(.10) /NOORIGIN
/DEPENDENT fulledcost
/METHOD=STEPWISE associatedegrees bachelordegrees masterdegrees doctordegrees firstprofdegrees awardslessthan1yr awards1yrto2yr awards2yrto4yr postbacccertificates postmastcertificates
firstprofcertificates .
Regression notes
Output created 30-AUG-2008 23:59:58
Comments
Input Data C:\Documents and Settings
ate.johnson\Desktop\Delta Project Materials\delta truncated database.sav
Active dataset DataSet1
Filter IsGrouped = 0 and sector=1 and AcademicYear = 2006 (FILTER)
Weight <none>
Split file <none>
N of rows in working data file 504
Missing value handling Definition of missing User-defined missing values are treated as missing.
Cases used Statistics are based on cases with no missing values for any variable used.
Syntax REGRESSION
/MISSING LISTWISE
/STATISTICS COEFF OUTS R ANOVA /CRITERIA=PIN(.05) POUT(.10) /NOORIGIN
/DEPENDENT fulledcost
/METHOD=STEPWISE associatedegrees bachelordegrees masterdegrees doctordegrees firstprofdegrees awardslessthan1yr awards1yrto2yr awards2yrto4yr postbacccertificates postmastcertificates firstprofcertificates .
Variables entered/removed* Model Variables entered Number of degrees, certificates Variables removed Method
1 Doctoral degrees . Stepwise (Criteria: Probability-of-F-to-enter <= .050,
Probability-of-F-to-remove >= .100).
2 Bachelor’s degrees . Stepwise (Criteria: Probability-of-F-to-enter <= .050, Probability-of-F-to-remove >= .100).
3 First professional degrees . Stepwise (Criteria: Probability-of-F-to-enter <= .050, Probability-of-F-to-remove >= .100).
4 Associate degrees . Stepwise (Criteria: Probability-of-F-to-enter <= .050, Probability-of-F-to-remove >= .100).
5 Post-master’s certificates . Stepwise (Criteria: Probability-of-F-to-enter <= .050, Probability-of-F-to-remove >= .100).
6 Master’s degrees . Stepwise (Criteria: Probability-of-F-to-enter <= .050, Probability-of-F-to-remove >= .100).
*Dependent variable: Full educational costs
Model summary
Model R R square Adjusted R square Std. error of estimate
1 .892(a) .795 .795 64105487.56140 2 .918(b) .842 .842 56302677.88338 3 .932(c) .869 .868 51316111.34112 4 .937(d) .878 .877 49664525.03071 5 .940(e) .883 .882 48672339.67941 6 .940(f) .884 .882 48514380.78693
Predictors: (Constant), Number of a. Doctoral degrees
b. Doctoral degrees, bachelor’s degrees
c. Doctoral degrees, bachelor’s degrees, first professional degrees
d. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees
e. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees, post-mas- ter’s certificates
f . Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees, post-mas- ter’s certificates, master’s degrees
ANOVA (Dependent variable: Full educational costs)
Model Sum of squares df Mean square F Sig. 1 Regression 7985754003247210000.000 1 7985754003247210000.000 1943.236 .000(a) Residual 2058866281278201000.000 501 4109513535485432.000 Total 10044620284525410000.000 502 2 Regression 8459624516105530000.000 2 4229812258052767000.000 1334.329 .000(b) Residual 1584995768419877000.000 500 3169991536839755.000 Total 10044620284525410000.000 502 3 Regression 8730581986221300000.000 3 2910193995407103000.000 1105.133 .000(c) Residual 1314038298304103000.000 499 2633343283174557.000 Total 10044620284525410000.000 502 4 Regression 8816270891355540000.000 4 2204067722838885000.000 893.578 .000(d) Residual 1228349393169871000.000 498 2466565046525846.000 Total 10044620284525410000.000 502 5 Regression 8867228949541110000.000 5 1773445789908223000.000 748.606 .000(e) Residual 1177391334984295000.000 497 2368996649867798.000 Total 10044620284525410000.000 502 6 Regression 8877212293528310000.000 6 1479535382254719000.000 628.614 .000(f) Residual 1167407990997098000.000 496 2353645143139310.000 Total 10044620284525410000.000 502
Predictors: (Constant), Number of: a. Doctoral degrees
b. Doctoral degrees, bachelor’s degrees
c. Doctoral degrees, bachelor’s degrees, first professional degrees
d. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees
e. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees, post-mas- ter’s certificates
f. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees, post-mas- ter’s certificates, master’s degrees
Coefficients (Dependent variable: Full educational costs)
Model Degrees, certificates
Unstandardized coefficients
Standardized
coefficients t Sig. B Std. error Beta B Std. error 1 (Constant) 66569398.743 3071440.741 21.674 .000 Doctoral degrees 1057010.200 23978.191 .892 44.082 .000 2 (Constant) 37834836.688 3577765.646 10.575 .000 Doctoral degrees 755180.619 32448.952 .637 23.273 .000 Bachelor’s degrees 29062.025 2376.978 .335 12.226 .000 3 (Constant) 30239817.791 3345749.351 9.038 .000 Doctoral degrees 494528.080 39178.646 .417 12.622 .000 Bachelor’s degrees 33244.303 2205.340 .383 15.074 .000
First professional degrees 261945.691 25823.460 .248 10.144 .000
4 (Constant) 24659664.814 3373632.713 7.310 .000
Doctoral degrees 480982.512 37987.280 .406 12.662 .000
Bachelor’s degrees 34792.379 2150.461 .401 16.179 .000
First professional degrees 267150.936 25007.942 .253 10.683 .000
Associate degrees 32037.665 5435.567 .093 5.894 .000
5 (Constant) 22552862.265 3337295.050 6.758 .000
Doctoral degrees 452687.577 37724.947 .382 12.000 .000
Bachelor’s degrees 34817.924 2107.507 .401 16.521 .000
First professional degrees 267454.328 24508.427 .253 10.913 .000
Associate degrees 33173.459 5332.603 .097 6.221 .000
Post-master’s certificates 282691.150 60952.006 .075 4.638 .000
6 (Constant) 22374687.826 3327589.136 6.724 .000
Doctoral degrees 451781.030 37605.093 .381 12.014 .000
Bachelor’s degrees 30779.584 2873.600 .354 10.711 .000
First professional degrees 250505.028 25777.871 .237 9.718 .000
Associate degrees 33817.832 5324.497 .098 6.351 .000
Post-master’s certificates 257166.164 62005.434 .068 4.147 .000
Excluded variables (Dependent variable: Full educational costs)
Tolerance Model Degrees, awards Beta in t Sig.
Partial correlation
Collinearity statistics 1 Associate degrees .060(a) 3.008 .003 .133 .996
Bachelor’s degrees .335(a) 12.226 .000 .480 .421
Master’s degrees .313(a) 11.513 .000 .458 .437
First professional degrees .179(a) 6.187 .000 .267 .454
Awards less than 1 year .056(a) 2.773 .006 .123 .999
Awards of 1-2 years .048(a) 2.371 .018 .105 .999
Awards of 2-4 years .029(a) 1.412 .159 .063 1.000
Post-baccalaureate certificates .028(a) 1.365 .173 .061 .984
Post-master’s certificates .071(a) 3.369 .001 .149 .901
First professional certificates .006(a) .283 .778 .013 .922
2 Associate degrees .087(b) 4.984 .000 .218 .982
Master’s degrees .175(b) 5.108 .000 .223 .257
First professional degrees .248(b) 10.144 .000 .413 .438
Awards less than 1 year .078(b) 4.423 .000 .194 .989
Awards of 1-2 years .074(b) 4.188 .000 .184 .986
Awards of 2-4 years .025(b) 1.436 .152 .064 .999
Post-baccalaureate certificates .001(b) .081 .936 .004 .970
Post-master’s certificates .070(b) 3.807 .000 .168 .901
First professional certificates .040(b) 2.167 .031 .097 .902
3 Associate degrees .093(c) 5.894 .000 .255 .981
Master’s degrees .081(c) 2.411 .016 .107 .232
Awards less than 1 year .081(c) 5.126 .000 .224 .989
Awards of 1-2 years .072(c) 4.469 .000 .196 .985
Awards of 2-4 years .033(c) 2.022 .044 .090 .998
Post-baccalaureate certificates .000(c) -.004 .997 .000 .970
Post-master’s certificates .070(c) 4.201 .000 .185 .901
First professional certificates .017(c) 1.009 .314 .045 .885
4 Master’s degrees .094(d) 2.901 .004 .129 .231
Awards less than 1 year .030(d) 1.328 .185 .059 .475
Awards of 1-2 years .024(d) 1.225 .221 .055 .627
Awards of 2-4 years .028(d) 1.772 .077 .079 .995
Post-baccalaureate certificates .003(d) .200 .842 .009 .969
Post-master’s certificates .075(d) 4.638 .000 .204 .899
First professional certificates .018(d) 1.088 .277 .049 .885
5 Master’s degrees .067(e) 2.060 .040 .092 .222
Awards less than 1 year .029(e) 1.295 .196 .058 .475
Awards of 1-2 years .024(e) 1.263 .207 .057 .627
Awards of 2-4 years .030(e) 1.944 .052 .087 .994
Post-baccalaureate certificates .007(e) .455 .650 .020 .966
First professional certificates .028(e) 1.695 .091 .076 .872
6 Awards less than 1 year .026(f) 1.166 .244 .052 .473
Awards of 1-2 years .024(f) 1.263 .207 .057 .627
Awards of 2-4 years .026(f) 1.654 .099 .074 .971
Post-baccalaureate certificates -.002(f) -.146 .884 -.007 .885
Predictors in the model: (Constant) Number of: a. Doctoral degrees
b. Doctoral degrees, bachelor’s degrees
c. Doctoral degrees, bachelor’s degrees, first professional degrees
d. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees
e. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees, post-mas- ter’s certificates
f. Doctoral degrees, bachelor’s degrees, first professional degrees, associate degrees, post-mas- ter’s certificates, master’s degrees
Summary of alternative regression results using different dependent variables with and without constant for degrees and certificates
Dependent variable Independent variables remaining in stepwise regression Unstandardized coefficients Standardized coefficients t Sig. Relative derived “cost” (bachelor’s =1)
Full educational costs with constant
R-squared = .884 B Std. error Beta (Constant) $22,374,688 $3,327,589 6.72 0.000 Doctoral degrees $451,781 $37,605 0.38 12.01 0.000 14.7 Bachelor’s degrees $30,780 $2,874 0.35 10.71 0.000 1.0
First professional degrees $250,505 $25,778 0.24 9.72 0.000 8.1
Associate degrees $33,818 $5,324 0.10 6.35 0.000 1.1
Post-master’s certificates $257,166 $62,005 0.07 4.15 0.000 8.4
Master’s degrees $16,673 $8,096 0.07 2.06 0.040 0.5 Full educational costs without constant
B Std. error Beta
Bachelor’s degrees $44,408 $1,642 0.53 27.04 0.000 1.0
First professional degrees $298,381 $25,063 0.23 11.91 0.000 6.7
Doctoral degrees $340,423 $36,291 0.24 9.38 0.000 7.7 Associate degrees $42,476 $5,314 0.10 7.99 0.000 1.0 Post-master’s certificates $355,988 $63,015 0.08 5.65 0.000 8.0 Awards of 2-4 years $257,613 $113,556 0.03 2.27 0.024 5.8 First professional certificates $582,189 $294,176 0.03 1.98 0.048 13.1
Direct instruction expenditures with constant
R-squared = .898
B Std. error Beta
(Constant) $10,365,008 $2,144,905 4.83 0.000
Doctoral degrees $387,200 $24,250 0.47 15.97 0.000 20.7
First professional degrees $182,279 $15,750 0.25 11.57 0.000 9.7
Bachelor’s degrees $18,713 $1,355 0.31 13.81 0.000 1.0
Associate degrees $16,795 $3,428 0.07 4.90 0.000 0.9
Post-master’s certificates $178,855 $39,172 0.07 4.57 0.000 9.6 Direct instructional expenditures without constant
B Std. error Beta
Doctoral degrees $342,860 $22,676 0.37 15.12 0.000 14.9
Bachelor’s degrees $22,998 $1,028 0.42 22.36 0.000 1.0
First professional degrees $196,769 $15,664 0.24 12.56 0.000 8.6
Associate degrees $15,183 $4,315 0.05 3.52 0.000 0.7
Post-master’s certificates $203,589 $39,500 0.07 5.15 0.000 8.9
Dependent variable Independent variables remaining in stepwise regression Unstandardized coefficients Standardized coefficients t Sig. Relative derived “cost” (bachelor’s =1)
Gross tuition, state, federal, and local appropriations with constant
R-squared = .918 B Std. error Beta (Constant) $20,060,541 $3,312,929 6.06 0.000 Doctoral degrees $578,806 $37,714 0.41 15.35 0.000 13.7 Bachelor’s degrees $42,221 $2,844 0.41 14.85 0.000 1.0
First professional degrees $212,306 $25,630 0.17 8.28 0.000 5.0
Associate degrees $22,829 $6,606 0.06 3.46 0.001 0.5 Master’s degrees $16,597 $7,921 0.06 2.10 0.037 0.4 First professional certificates $779,347 $281,628 0.04 2.77 0.006 18.5 Awards of 1-2 years $122,687 $55,285 0.04 2.22 0.027 2.9 Post-master’s certificates $131,671 $61,939 0.03 2.13 0.034 3.1 Gross tuition, state, federal, and local appropriations without constant
B Std. error Beta
Bachelor’s degrees $50,316 $2,598 0.52 19.36 0.000 1.0
Doctoral degrees $487,874 $35,817 0.29 13.62 0.000 9.7
First professional degrees $241,138 $26,074 0.16 9.25 0.000 4.8
Associate degrees $29,328 $6,748 0.06 4.35 0.000 0.6 Post-master’s certificates $181,221 $63,565 0.03 2.85 0.005 3.6 First professional certificates $879,537 $291,074 0.03 3.02 0.003 17.5 Awards of 1-2 years $158,121 $56,917 0.04 2.78 0.006 3.1 Master’s degrees $18,171 $8,196 0.06 2.22 0.027 0.4