....:....1....:....2....:....3....:....4....:....5....:....6....:....7....:....8

Source:

Gallant, A. Ronald (1987), Nonlinear Statistical Models, 
New York: John Wiley and Sons, p. 4.

....:....1....:....2....:....3....:....4....:....5....:....6....:....7....:....8

//D18   JOB NCS.ES.B4145,5GALLANT,COMPRESS=NO,PRTY=2
//STEP1 EXEC SAS,OPTIONS='LINESIZE=80'
//SAS.EB652SAS DD DSN=NCS.ES.B4139.GALLANT.EB652SAS,DISP=OLD
//SAS.SYSIN DD *
DATA EXAMPLE1;  INPUT T Y X1 X2 X3 ; CARDS;
                         1    0.98610    1     1     6.28
                         2    1.03848    0     1     9.86
                         3    0.95482    1     1     9.11
                         4    1.04184    0     1     8.43
                         5    1.02324    1     1     8.11
                         6    0.90475    0     1     1.82
                         7    0.96263    1     1     6.58
                         8    1.05026    0     1     5.02
                         9    0.98861    1     1     6.52
                        10    1.03437    0     1     3.75
                        11    0.98982    1     1     9.86
                        12    1.01214    0     1     7.31
                        13    0.66768    1     1     0.47
                        14    0.55107    0     1     0.07
                        15    0.96822    1     1     4.07
                        16    0.98823    0     1     4.61
                        17    0.59759    1     1     0.17
                        18    0.99418    0     1     6.99
                        19    1.01962    1     1     4.39
                        20    0.69163    0     1     0.39
                        21    1.04255    1     1     4.73
                        22    1.04343    0     1     9.42
                        23    0.97526    1     1     8.90
                        24    1.04969    0     1     3.02
                        25    0.80219    1     1     0.77
                        26    1.01046    0     1     3.31
                        27    0.95196    1     1     4.51
                        28    0.97658    0     1     2.65
                        29    0.50811    1     1     0.08
                        30    0.91840    0     1     6.11
DATA WORK01;  SET EXAMPLE1;
IF T=2 OR T=6 OR T=11 OR T=14 THEN OUTPUT; DELETE;
PROC NLIN DATA=WORK01 METHOD=GAUSS ITER=50 CONVERGENCE=1.0E-5;
PARMS T1=0 T2=0 T3=-1 T4=-1;
MODEL Y=T1*X1+T2*X2+T4*EXP(T3*X3);
DER.T1=X1; DER.T2=X2; DER.T3=T4*X3*EXP(T3*X3); DER.T4=EXP(T3*X3);