/* energy.sas */
/* energy usage examples */
/* part 1: houses of either design type */
data energy1;
   input gas type $ design $;
   if design='either';
cards;
11.4 standard either
13.9 standard either
13.9 standard either
14.0 standard either
15.3 standard either
18.0 standard either
18.0 standard either
18.1 standard either
18.9 standard either
19.0 standard either
19.0 standard either
21.7 standard either
8.3  extra either
11.7 extra either
12.7 extra either
13.0 extra either
13.4 extra either
13.6 extra either
13.7 extra either
13.7 extra either
13.8 extra either
14.6 extra either
15.3 extra either
15.6 extra either
16.0 extra either
18.8 extra either
12.3 standard solar
13.3 standard solar
13.7 standard solar
13.8 standard solar
14.9 standard solar
15.6 standard solar
15.9 standard solar
16.3 standard solar
16.5 standard solar
17.2 standard solar
17.5 standard solar
17.6 standard solar
17.8 standard solar
17.9 standard solar
18.0 standard solar
19.9 standard solar
10.5 extra solar
11.3 extra solar
11.4 extra solar
12.6 extra solar
13.0 extra solar
14.5 extra solar
15.2 extra solar
15.7 extra solar
15.7 extra solar
17.6 extra solar
19.0 extra solar
;   
proc univariate data=energy1 normal nextrval=5;
   class type;
   var gas;
   ods select BasicMeasures TestsForNormality ExtremeValues Quantiles;
title 'energy usage summary (both house designs)';
proc ttest data=energy1 ci=none
   plots (shownull only) = (histogram boxplot interval qq);
   class type;
   var gas;
run;
/* ------------------------------------------------- */   
/* part 2: houses of solar design */
data energy2;
   input gas type $ design $;
   if design='solar';
cards;
11.4 standard either
13.9 standard either
13.9 standard either
14.0 standard either
15.3 standard either
18.0 standard either
18.0 standard either
18.1 standard either
18.9 standard either
19.0 standard either
19.0 standard either
21.7 standard either
8.3  extra either
11.7 extra either
12.7 extra either
13.0 extra either
13.4 extra either
13.6 extra either
13.7 extra either
13.7 extra either
13.8 extra either
14.6 extra either
15.3 extra either
15.6 extra either
16.0 extra either
18.8 extra either
12.3 standard solar
13.3 standard solar
13.7 standard solar
13.8 standard solar
14.9 standard solar
15.6 standard solar
15.9 standard solar
16.3 standard solar
16.5 standard solar
17.2 standard solar
17.5 standard solar
17.6 standard solar
17.8 standard solar
17.9 standard solar
18.0 standard solar
19.9 standard solar
10.5 extra solar
11.3 extra solar
11.4 extra solar
12.6 extra solar
13.0 extra solar
14.5 extra solar
15.2 extra solar
15.7 extra solar
15.7 extra solar
17.6 extra solar
19.0 extra solar
;   
proc univariate data=energy2 normal nextrval=5;
   class type;
   var gas;
   ods select BasicMeasures TestsForNormality ExtremeValues Quantiles;
title 'energy usage summary (solar house designs)';
proc ttest data=energy2 ci=none
   plots (shownull only) = (histogram boxplot interval qq);
   class type;
   var gas;
run;