The latent variable covariance matrix is not positive difine?

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Mark Shevlin Popular answer

I found this page to be very useful

http://www2.gsu.edu/~mkteer/npdmatri.html

Mark Shevlin

Kirk Becker

I have run into this (for factor analysis) when working with missing data and when the correlation matrix was computed using pairwise deletion. My understanding is that a set of correlations can be internally inconsistent/impossible in this situation.

Sanjay Singh

You have to perform a series of check in your dataset, like missing values, multicollinearity, variance of items. It's goes in iterative manner

Zainudin Awang

Covariance Matrix is not positive definite means the factor structure of your dataset does not make sense to the model that you specify. The problem might be due to many possibilities such as error in data entry, duplicate input, multiple entry etc.