Getting Started Example 1 for PROC NLMIXED
/****************************************************************/
/* S A S S A M P L E L I B R A R Y */
/* */
/* NAME: nlmgs1 */
/* TITLE: Getting Started Example 1 for PROC NLMIXED */
/* PRODUCT: STAT */
/* SYSTEM: ALL */
/* KEYS: Logistic growth curve with random effects */
/* Growth data */
/* Continuous response */
/* PROCS: NLMIXED */
/* DATA: Orange tree data, Draper and Smith (1981) */
/* */
/* SUPPORT: Oliver Schabenberger */
/* REF: */
/* MISC: */
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data tree;
input tree day y;
datalines;
1 118 30
1 484 58
1 664 87
1 1004 115
1 1231 120
1 1372 142
1 1582 145
2 118 33
2 484 69
2 664 111
2 1004 156
2 1231 172
2 1372 203
2 1582 203
3 118 30
3 484 51
3 664 75
3 1004 108
3 1231 115
3 1372 139
3 1582 140
4 118 32
4 484 62
4 664 112
4 1004 167
4 1231 179
4 1372 209
4 1582 214
5 118 30
5 484 49
5 664 81
5 1004 125
5 1231 142
5 1372 174
5 1582 177
;
proc nlmixed data=tree;
parms b1=190 b2=700 b3=350 s2u=1000 s2e=60;
num = b1+u1;
ex = exp(-(day-b2)/b3);
den = 1 + ex;
model y ~ normal(num/den,s2e);
random u1 ~ normal(0,s2u) subject=tree;
run;