请教:随机数函数normal

shiyiming

use the means procedure, and have a look at the value of STD, which is sqrt(variance).

shiyiming

Yes, horse1, after the dataset being created, we can proc means it for STD value.
How about before the dataset being created, how did you know it is sqrt(30) for the 'call randgen', beforehand?

shiyiming

晕，SAS帮助里面关于call randgen的参数写得很清楚啊，关于正态分布的第二个参数是标准差而不是方差。

shiyiming

晕,的确是写了.
Table 20.2: Parameter Assignments for Distributions里面有. <!-- s:lol: --><img src="{SMILIES_PATH}/icon_lol.gif" alt=":lol:" title="Laughing" /><!-- s:lol: -->

shiyiming

data a;
retain seed 0 ;
do i =1 to 1000;
call rannor(seed,x);
output;
end;
proc print;
run;

shiyiming

to einstein_817:
不对,你那个程序用proc means算出来的均值和方差不对.