求助！广义相加模型！（简单sas程序 老是报错）-经管之家官网！

data a;
input rain pressure wind T Tmax Tmin rh sunCase ;
cards;
0 1032.4 0.5 -1.5 3.4 -4.9 56 7.5 8
0 1021.6 1.1 1.8 7.8 -2.7 59 7.8 17
0 1019.6 1.4 4.3 11.4 -0.5 64 7.7 7
0 1025.9 1.3 4.3 9.1 0.6 67 6.6 12
0 1024.7 0.7 2.9 5.9 2.1 63 1.8 10
0 1023 0.6 4 10.4 0 76 7.2 17
......
；
proc gam;model case=spline(rain)spline(pressure)spline(wind)spline(sun)/dist=poissonlink=log ;score data=a out=b;proc print data= b;run;
SAS输出结果：ERROR: Value of DIST= opt is unrecognized. Only GAUSSIAN, POISSON, BINOMIAL, BINARY, LOGIT, INVGAUSSIAN, and GAMMA are allowed.NOTE: The data set WORK.B has 0 observations and 0 variables.WARNING: Data set WORK.B was not replaced because new file is incomplete.NOTE: PROCEDURE GAM used (Total process time): real time 0.00 seconds cpu time 0.00 seconds
15393proc print data= b;15394run;NOTE: No variables in data set WORK.B.
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