st: Question II about -drawnorm- for two normally distributed variables

[tiago.pereira@incor.usp.br]

Dear all,

Would it be possible to you to explain why I am getting this:

mean1 = 0.4+-0.05 (+-variance)
mean2 = 0.2+-0.02 (+-variance)

covariance = 0.11

corr2data cholesterol1 cholesterol2, means(0.4  0.2) cov(0.05, 0.11\ 0.11,
0.02) cstorage(full) n(100)

. 0.05, 0.11\ 0.11, 0.02 not positive (semi)definite
. r(506);



Any idea?

thank you!

Tiago
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