Plot the Covariance MatrixΒΆ

You might wish to examine how the various parameters are correlated with each other. You can do this by plotting the covariance matrix using visualize.covariance():

import visualize
visualize.covariance()

This will produce an enormous plot showing correlations between all of the model parameters. The plot is too big to reproduce here, but you can use Preview to zoom in on any panel of interest. There is evidence that DeltaRA for Lens0 is highly anti-correlated with DeltaRA for Source0. This is expected since the source position has been fixed relative to the lens position in this model fit. The same holds true for DeltaDec.