nonlin1.sas

SAS for Windows统计分析系统教程,里面有源码

title 'Exponential Curve';
data nonlin1;
  input x y @@;
cards;
 1 19250  2 17420  3 12360
 4 11270  5  7310  6  4690
 7  4000  8  3810  9  2840
10  2760 11   620 12   610
13   408 14   428 15   305
;
proc nlin best=50 method=marquardt;
  der.a=exp(b*x);
  der.b=a*x*exp(b*x);
  model y=a*exp(b*x);
  output out=a predicted=yhat residual=yresid;
  parameters a=26400 to 26500 by 5 b=-0.3 to -0.25 by 0.1;
run;