Hi all,

I'm examining the effect of fire occurrence on visits to National Parks and Forests using a panel dataset. Since my Y variable is a count variable, I intend to do so using a negative binomial fixed effects model. However, my units of analysis are not iid; there is spatial correlation between. I created a spatial weighting matrix on ArcMap which has 3 columns: my unit ID, neighboring unit ID, and weight. However, I'm having a hard time doing anything with it on Stata. I have two questions:

1) When I do spmat import using "weights.dta", I keep getting errors that say "error in line 1 of file." I don't know why that's happening. Here's what's in line 1:
realpudfid nid weight
248 249 .2736487

2) All I'm trying to do is cluster standard errors properly. Is it even possible to do this with a negative binomial model? Could someone walk me through how?

Thank you so much!