sds(vector)           standard deviations of generated variables

Examples


    Generate 2000 independent observations (x,y); x with mean 2 and standard
    deviation .5; y with mean 3 and standard deviation 2.


        . matrix m = (2,3)
        . matrix sd = (.5,2)
        . drawnorm x y, n(2000) means(m) sds(sd)
        . summarize


    Draw a sample of 1000 observations from a bivariate standard normal
    distribution, with correlation 0.5.


        . clear
        . matrix C = (1, .5 \ .5, 1)
        . drawnorm x y, n(1000) corr(C)
        . summarize


    Equivalently,


        . clear
        . matrix C = (1, .5, 1)
        . drawnorm x y, n(1000) corr(C) cstorage(lower)
        . summarize

夏目贵志 发表于 2015-9-12 05:52
sds需要你提供一个vector。sqrt(3)不是vector。可以参考帮助文件里的例子：