How does OpenMx handle missing data with WLS?

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No user picture. jpritsker Joined: 09/27/2020
I might be missing something obvious, but as far as I can tell, this isn't explicated anywhere. How does OpenMx deal with missing data for WLS? Is it listwise/pairwise or is the polychoric covariance matrix computed using FIML?
Replied on Mon, 09/28/2020 - 14:13
Picture of user. jpritikin Joined: 05/23/2012

mxData offers an naAction option. If you don't exclude missing data then it is ignored pairwise. There isn't really a correct way, math-wise, to handle inconsistent sample sizes in a covariance matrix. It just does the best it can.
Replied on Fri, 10/02/2020 - 11:09
Picture of user. AdminNeale Joined: 03/01/2013

HI

It's FIML-pairwise. FIML is used to estimate the polychorics, but the variables go into the ark two-by-two, so it isn't FIML. Note, however, that this is likely a lot better than listwise deletion throughout.