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[Lance Wollenberg]

Does anyone have any context as to why the below listed matrix is listed as not positive-definite

 

ranef(block(nV, nCl0, nClss) = c(0.663, 0.6934, 0.746, 0.764, 0.388, 0.634), diag (nTlag, nKa, Kind )= c(0.304, 0.965, 1.25))

[smouksassi1]

Hi Lance,

was this omega estimated by nlme or nonmem ?

may times because of precision issue ( not enough significant digits output an Omega matrix can be flagged as not positive definite. Make sure that you use all the digits from the full omega outputs.

Bests,

Samer