Correlation matrix is not positive definite and singular?
Apr 26, 2019 4:16 AM(2171 views)
I am trying to do a factor analysis (PCA) on a large data set. It has 181 columns and 163 rows, values are between -6 and 8. I have started the factor analysis and the eigenvalues and scree plot looks good.Below all the factors it says: "Warning: the Correlation matrix is not positive definite". Can someone help me understand what it means?
I try to perform the analysis using Maximum Likelihood and Common Factor Analysis with a Varimax rotations method. But I get an error message saying: "Maximum likelihood method requires a nonsingular correlation matrix. Switching to principal components method may fix the problem."
I am only a beginner in JMP but I appreciate any help on this matter.