statsmodels.genmod.cov_struct.Nested.covariance_matrix

Nested.covariance_matrix(expval, index) [source]

Returns the working covariance or correlation matrix for a given cluster of data.

Parameters:	endog_expval (array-like) – The expected values of endog for the cluster for which the covariance or correlation matrix will be returned index (integer) – The index of the cluster for which the covariane or correlation matrix will be returned
Returns:	M (matrix) – The covariance or correlation matrix of endog is_cor (bool) – True if M is a correlation matrix, False if M is a covariance matrix