我本来是mixed logit之后直接用stata的wtp命令算支付意愿的，老师要用蒙特卡洛模拟来计算wtp。

我用变量的均值和相关系数矩阵生成多维正态分布随机向量以后，这个生成的有错吗？接下来要怎么用simulate语句分析呢？

. set obs 10000
number of observations (_N) was 7,272, now 10,000

. set matsize 10000

. gen ORG = rnormal(0.333,0.471)

. gen PEST = rnormal(0.333,0.471)

. gen RGB = rnormal(0.223,0.416)

. gen NAB = rnormal(0.223,0.416)

. gen ASC = rnormal(0.333,0.471)

. mkmat ORG PEST RGB NAB ASC,matrix(variab)

. mat rho =(1,0.2450,0.1843,0.1857,-0.5000\0.2450,1,0.1864,0.1864,-0.5000\0.1843,0.1864,1,-0.2873,-0.3790\0.1857,0.1864,-0
> .2873,1,-0.3790\-0.5000,-0.5000,-0.3790,-0.3790,1)

. mat L =cholesky(rho)

. mat X = L * variab'

. mat A = X'

. svmat A