options ls=78;

data cls9;

      infile 'class9.dat';

      input sn income hsGPA SAT cGPA coyrs evaluation;

      if (sn=109) then delete;

      tcoyrs=sqrt(coyrs);

run;

proc print data=cls9;

run;

proc plot data=cls9;

      plot income*hsGPA income*SAT income*cGPA income*coyrs income*tcoyrs income*evaluation;

      title 'Scatterplots for All Variables by Income';

run;

proc corr data=cls9;

      var income hsGPA SAT cGPA coyrs tcoyrs evaluation;

      title 'Correlations for All Variables';

run;

proc reg data=cls9;

      model income=tcoyrs;

      var hsGPA SAT cGPA evaluation;

      title 'Regression of Income by CoYrs';

run;

      plot income*tcoyrs pred.*tcoyrs /overlay;

      title 'Plot of Income by Company Years';

run;

      plot r.*hsGPA;

      title 'Plot of residuals by hs GPA';

run;

      plot r.*SAT;

      title 'Plot of residuals by SAT';

run;

      plot r.*cGPA;

      title 'Plot of residuals by c GPA';

run;

      plot r.*evaluation;

      title 'Plot of residuals by evaluation';

run;

proc reg data=cls9;

      model income=tcoyrs SAT;

      var hsGPA cGPA evaluation;

      title 'Chrissy Regression by CoYrs and SAT';

run;

      plot r.*pred.;

      title 'Plot of residual by predicted';

run;

      plot r.*hsGPA;

      title 'Plot of residuals by hs GPA';

run;

      plot r.*cGPA;

      title 'Plot of residuals by c GPA';

run;

      plot r.*evaluation;

      title 'Plot of residuals by evaluation';

run;

proc reg data=cls9;

      model income=tcoyrs SAT evaluation;

      var hsGPA cGPA;

      title 'Chrissy Regression by CoYrs, SAT, and Evaluation';

run;

      plot r.*pred.;

      title 'Plot of residual by predicted';

run;

      plot r.*hsGPA;

      title 'Plot of residuals by hs GPA';

run;

      plot r.*cGPA;

      title 'Plot of residuals by c GPA';

run;

proc reg data=cls9;

      model income=tcoyrs SAT evaluation hsGPA;

      var cGPA;

      title 'Chrissy Regression by CoYrs, SAT, Evaluation, and hsGPA';

run;

      plot r.*pred.;

      title 'Plot of residual by predicted';

run;

      plot r.*cGPA;

      title 'Plot of residuals by c GPA';

run;

proc reg data=cls9;

      model income=tcoyrs SAT evaluation hsGPA cGPA /r stb pcorr1 scorr1;

      title 'Chrissy Regression by All Variables';

run;

      plot r.*pred.;

      title 'Plot of residual by predicted';

run;

quit;