"Conformability error" while using xsmle

Hi Statalist,

With Stata /SE 14.1, I'm using xsmle with a fixed effects regresson model. When the command (xsmle dv iv i.year, model(sar) wmatrix(contig_county) vce(robust) noeff fe) runs, Stata returns this:

*: 3200 conformability error
_xsmle_est(): - function returned error
<istmt>: - function returned error
r(3200);

For my spatial weights matrix, I created an spmat object for U.S. counties based on the code described in Drukker et al. 2013, "Creating and managing spatial weighting matrix with the spmat command." As background, the summary stats for this object are as follows:

. spmat sum contig_county

Summary of spatial-weighting object contig_county
--------------------------------------------------
Matrix | Description
---------------+----------------------------------
Dimensions | 3233 x 3233
Stored as | 3233 x 3233
Values |
min | 0
min>0 | .0714286
mean | .0003084
max | 1
--------------------------------------------------
warning: spatial-weighting matrix contains 10 islands

Any help? Has anyone gotten this particular error message before?

Sincerely,
Ethan