title 'A One-Way Layout for Water Salinity';
title2 'Problem 12.4 p493';

options ls=75 ps=60 pageno=1 nocenter;

***************************************************************;
* Water salinity measurements from 3 lagoons
* 12 measurements from Asite, 8 from Bsite, 10 from Csite
* SAS needs a categorical variable (``Group'') in one column
*   and a numerical variable (yy=Salinity) in another column
***************************************************************;

data water;
     input group$ yy;
datalines;
     Asite  37.54
     Asite  37.01
     Asite  36.71
     Asite  37.03
     Asite  37.32
     Asite  37.01
     Asite  37.03
     Asite  37.70
     Asite  37.36
     Asite  36.75
     Asite  37.45
     Asite  38.85
     Bsite  40.17
     Bsite  40.80
     Bsite  39.76
     Bsite  39.70
     Bsite  40.79
     Bsite  40.44
     Bsite  39.79
     Bsite  39.38
     Csite  39.21       
     Csite  39.21       
     Csite  39.05       
     Csite  38.24       
     Csite  38.53       
     Csite  38.71       
     Csite  38.89       
     Csite  38.66       
     Csite  38.51       
     Csite  40.08       
     run;

proc print;
     title3 'The data as SAS sees it';
     run;

proc boxplot;
     title3 'SIDE-BY-SIDE BOX PLOTS for three lagoons';
     plot yy*group;
     run;

proc glm;
     title3 'TESTING HOMOGENEITY OF MEANS';
     title4 'ALSO COMPARING MEANS BY LSD and TUKEY METHODS';
     class group;
     model yy=group;
     means group / lsd tukey;
     run;