Hi, I'm trying to use the "spdep" package function globalG.test() to compute Z-scores using Get-Ord Gi* for a data frame of temperature values for the Northeast (after creating the listw object required), however I keep receiving an error explaining that I can't input negative values. I'm basically trying to mimic ArcGIS' "Hot Spot Analysis" and am wondering if anyone knows of a built-in function or package that can do this or a method that works for you. I could write a very large program using the Get-Ord local statistic equation, however I'm looking for a more efficient solution. Thanks, -- Daniel Bishop BS, Cornell University '10 MS Candidate, SUNY ESF '13 -- View this message in context: http://r.789695.n4.nabble.com/Getis-Ord-Gi-Hot-Spot-Analysis-tp3659713p3659713.html Sent from the R help mailing list archive at Nabble.com.