options linesize=70 nodate;
data hamster;
   infile "c:/datasets/hamster.txt" firstobs=4;
   input hiber lifetime;

proc print;

* Define properties of points and lines;
symbol1 v=dot c=blue h=0.5; * Points;
symbol2 ci=red;             * Regression line;
symbol3 ci=blue;            * Lower prediction limit;
symbol4 ci=blue;            * Upper prediction limit;
symbol5 ci=green;           * Lower confidence limit;
symbol6 ci=green;           * Upper confidence limit;

* Obtain simple linear regression model;
proc reg;
   
   * Obtain x transpose x and xtranspose 
     x inverse matrices.  Show comfidence limits for mean
     and confidence limits for new observations.
     Use 95% confidence intervals for both;
   model lifetime=hiber / xpx i clb alpha=0.05;

   * Plot regression line with confidence 
     and prediction intervals;
   plot lifetime*hiber / conf pred;

run;
quit;