st: missing values after splagvar

["Andrade de Sa Saraly" <saraly.andrade@env.ethz.ch>]

Dear all,

I have a panel dataset for all counties of a given country and I am trying to see whether deforestation in the northern counties can be explained, among other factors, by expansion of a given crop in more southern counties.

For this analysis I thought about using spatial methods. I therefore constructed an inverse-distance weight matrix using -spwmatrix- (from SSC):

. spwmatrix gecon latitude longitude, wname(W) wtype(inv) cart rowstand eignvar(eigen).

Up to this point, everything seems to work fine.
Then I try to created spatial lags of my dependent variable (cleared) and some independent variables (cattle, pasture, roads, etc) using -splagvar- (also from SSC):

. splagvar cleared, wname(W_n) wfrom(Mata) ind(cattle natpast plpast pop gdpcap avroads sgcn soya) order(2)

My problem is that, at this stage, there are only missing values for the spatial-lagged variables.

Do any of you have an idea about what I might be doing wrong?

Thank you in advance,
Saraly

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