The FORECAST Procedure

Controlling the Forecasting Method

The METHOD= option controls which forecasting method is used. The TREND= option controls the degree of the time trend model used. For example, the following statements produce forecasts of SALES as in the preceding example but use the double exponential smoothing method instead of the default STEPAR method:

proc forecast data=past interval=month lead=10
              method=expo trend=2
              out=pred outfull outresid
              outest=est outfitstats;
   var sales;
   id date;
run;

proc print data=est;
run;

The PRINT procedure prints the OUTEST= data set for the EXPO method, as shown in Figure 16.7.

Figure 16.7: The OUTEST= Data Set for METHOD=EXPO

Obs _TYPE_ date sales
1 N JUL91 25
2 NRESID JUL91 25
3 DF JUL91 23
4 WEIGHT JUL91 0.1055728
5 S1 JUL91 11.427657
6 S2 JUL91 10.316473
7 SIGMA JUL91 0.2545069
8 CONSTANT JUL91 12.538841
9 LINEAR JUL91 0.1311574
10 SST JUL91 21.28342
11 SSE JUL91 1.4897965
12 MSE JUL91 0.0647738
13 RMSE JUL91 0.2545069
14 MAPE JUL91 1.9121204
15 MPE JUL91 -0.816886
16 MAE JUL91 0.2101358
17 ME JUL91 -0.094941
18 MAXE JUL91 0.3127332
19 MINE JUL91 -0.460207
20 MAXPE JUL91 2.9243781
21 MINPE JUL91 -4.967478
22 RSQUARE JUL91 0.930002
23 ADJRSQ JUL91 0.9269586
24 RW_RSQ JUL91 -0.243886
25 ARSQ JUL91 0.9178285
26 APC JUL91 0.0699557
27 AIC JUL91 -66.50591
28 SBC JUL91 -64.06816
29 CORR JUL91 0.9772418


See the section Syntax: FORECAST Procedure for other options that control the forecasting method. See the section Introduction to Forecasting Methods and the section Forecasting Methods for an explanation of the different forecasting methods.