1          OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;
 70         
 71         /* pain2.sas (2020 version) */
 72         title 'Covariance structure repeated measures analysis of the pain data';
 73         
 74         /* Read data from an old .xls spreadsheet */
 75         proc import datafile="/home/brunner0/441s20/Pain.xls"
 76                     out=ouch0 dbms=xls replace;
 77                     getnames=yes;
 
 NOTE: The import data set has 10 observations and 7 variables.
 NOTE: WORK.OUCH0 data set was successfully created.
 NOTE: PROCEDURE IMPORT used (Total process time):
       real time           0.00 seconds
       user cpu time       0.00 seconds
       system cpu time     0.01 seconds
       memory              1465.12k
       OS Memory           32152.00k
       Timestamp           03/04/2020 03:51:12 PM
       Step Count                        56  Switch Count  2
       Page Faults                       0
       Page Reclaims                     446
       Page Swaps                        0
       Voluntary Context Switches        17
       Involuntary Context Switches      0
       Block Input Operations            56
       Block Output Operations           264
       
 
 78         proc print;
 79         
 80         /*           Dose 1         Dose 2         Dose 3
 81                      ------         -----          ------
 82         Drug 1     Drug1Dose1     Drug1Dose2     Drug1Dose3
 83         Drug 2     Drug2Dose1     Drug2Dose2     Drug2Dose3   */
 84         
 
 NOTE: There were 10 observations read from the data set WORK.OUCH0.
 NOTE: PROCEDURE PRINT used (Total process time):
       real time           0.03 seconds
       user cpu time       0.04 seconds
       system cpu time     0.00 seconds
       memory              2190.71k
       OS Memory           31912.00k
       Timestamp           03/04/2020 03:51:12 PM
       Step Count                        57  Switch Count  0
       Page Faults                       0
       Page Reclaims                     107
       Page Swaps                        0
       Voluntary Context Switches        0
       Involuntary Context Switches      1
       Block Input Operations            0
       Block Output Operations           8
       
 
 85         data hurt;
 86              set ouch0;
 87              /* Need each response on a separate line for proc mixed. */
 88              array response{6} Drug1Dose1 -- Drug2Dose3;
 89              index = 0;
 90              do drug = 1 to 2;
 91                  do dose = 1 to 3;
 92                      index = index + 1;
 93                      pain = response{index};
 94                      output;
 95                  end;
 96              end;
 97              keep patient drug dose pain;
 98         
 
 NOTE: There were 10 observations read from the data set WORK.OUCH0.
 NOTE: The data set WORK.HURT has 60 observations and 4 variables.
 NOTE: DATA statement used (Total process time):
       real time           0.00 seconds
       user cpu time       0.00 seconds
       system cpu time     0.00 seconds
       memory              947.56k
       OS Memory           32428.00k
       Timestamp           03/04/2020 03:51:12 PM
       Step Count                        58  Switch Count  2
       Page Faults                       0
       Page Reclaims                     149
       Page Swaps                        0
       Voluntary Context Switches        15
       Involuntary Context Switches      0
       Block Input Operations            0
       Block Output Operations           264
       
 
 99         proc print data = hurt (obs=12); /* Just the first 12 lines */
 100        
 
 NOTE: There were 12 observations read from the data set WORK.HURT.
 NOTE: PROCEDURE PRINT used (Total process time):
       real time           0.02 seconds
       user cpu time       0.02 seconds
       system cpu time     0.00 seconds
       memory              735.25k
       OS Memory           32168.00k
       Timestamp           03/04/2020 03:51:12 PM
       Step Count                        59  Switch Count  0
       Page Faults                       0
       Page Reclaims                     61
       Page Swaps                        0
       Voluntary Context Switches        0
       Involuntary Context Switches      0
       Block Input Operations            0
       Block Output Operations           0
       
 
 101        proc mixed data=hurt;
 102             title2 'Unknown covariance structure';
 103             class drug dose;
 104             model pain = drug|dose;
 105             repeated / type=un subject=patient;
 106             /* Pairwise comparisons of marginal means for Dose */
 107             lsmeans dose / pdiff tdiff adjust = bon;
 108        run;
 
 NOTE: Convergence criteria met.
 NOTE: PROCEDURE MIXED used (Total process time):
       real time           0.12 seconds
       user cpu time       0.12 seconds
       system cpu time     0.00 seconds
       memory              1834.53k
       OS Memory           32940.00k
       Timestamp           03/04/2020 03:51:12 PM
       Step Count                        60  Switch Count  3
       Page Faults                       0
       Page Reclaims                     308
       Page Swaps                        0
       Voluntary Context Switches        22
       Involuntary Context Switches      1
       Block Input Operations            0
       Block Output Operations           312
       
 
 109        
 110        proc mixed data=hurt;
 111             title2 'Compound symmetry';
 112             class drug dose;
 113             model pain = drug|dose;
 114             repeated / type=cs subject=patient;
 115             lsmeans dose / pdiff tdiff adjust = bon;
 116        run;
 
 NOTE: Convergence criteria met.
 NOTE: PROCEDURE MIXED used (Total process time):
       real time           0.10 seconds
       user cpu time       0.10 seconds
       system cpu time     0.00 seconds
       memory              1272.65k
       OS Memory           32940.00k
       Timestamp           03/04/2020 03:51:12 PM
       Step Count                        61  Switch Count  3
       Page Faults                       0
       Page Reclaims                     207
       Page Swaps                        0
       Voluntary Context Switches        24
       Involuntary Context Switches      0
       Block Input Operations            0
       Block Output Operations           304
       
 
 117        
 118        /* F-tests from cs do not match up with the proc glm univariate tests
 119           in pain1.sas that are produced as a by-product of the multivariate
 120           approach. If you know how to read it, output from the code below
 121           shows that for this (simple and quite common) example, exact classical
 122           F-tests for the main effects do not exist unless the interaction is
 123           assumed to be absent. The proc mixed tests match what you get by making
 124           this assumption. It seems that the "by-product" univariate repeated
 125           measures analysis produced by proc glm is doing something else. I do
 126           not know exactly what it is doing, except that in every example I can
 127           find where all the classical tests DO exist, proc glm matches them.
 128           If we want the compound symmetry assumption, we will use proc mixed. */
 129        
 130        proc glm data=hurt noprint; /* Not showing the output */
 131             title2 'Trying classical the old fashioned way';
 132             class patient drug dose;
 133             model pain = patient drug|dose;
 134             random patient / test;
 135        run;
 
 136        
 137        
 138        
 139        OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;
 150