1. 6-4 Other Aspects of Regression
OPTIONS NODATE NOOVP NONUMBER;
DATA SALES;
INFILE 'C:\Users\korea\Desktop\Working Folder 2017\imen214-stats\ch06\data\sales.dat';
INPUT SALES TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING;
PROC CORR DATA=SALES;
VAR SALES;
WITH TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING;
TITLE 'CORRELATIONS OF DEPENDENT WITH INDENDENTS';
VAR TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING;
TITLE 'CORRELATIONS BETWEEN INDEPENDENT VARIABLES';
PROC REG DATA=SALES;
MODEL SALES=TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING/VIF R;
TITLE 'REGRESSION MODEL WITH ALL VARIABLES';
PROC RSQUARE DATA=SALES CP;
MODEL SALES=TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING
/ADJRSQ RMSE SSE SELECT=10;
TITLE 'ALL POSSIBLE REGRESSIONS';
MODEL SALES=TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING /selection=FORWARD slentry=0.25;
TITLE 'STEPWISE REGRESSION USING FORWARD SELECTION';
MODEL SALES=TIME POTENT ADVERT SHARE CHANGE ACCOUNTS WORKLOAD RATING /selection=BACKWARD;
TITLE 'STEPWISE REGRESSION USING BACKWARD ELIMINATION';
/selection=stepwise;
TITLE 'STEPWISE REGRESSION THE STEPWISE TECHNIQUE';
MODEL SALES=POTENT ADVERT SHARE ACCOUNTS/R;
MODEL SALES=POTENT ADVERT SHARE CHANGE ACCOUNTS/R;
MODEL SALES=TIME POTENT ADVERT SHARE CHANGE/R;
MODEL SALES=TIME POTENT ADVERT SHARE ACCOUNTS/R;
MODEL SALES=TIME POTENT ADVERT SHARE CHANGE WORKLOAD/R;
RUN; QUIT;