[R-sig-Geo] random samples of a grid

Hi, is there a way to sample an ESRI grid using random sample points? In the past I used ESRI's spatial analyst but I would like to switch all my analyses to R if possible. The grid is from the National Land Cover Dataset (30m res, 7 landcover classes). I had roadside points from which I extra

[R-sig-Geo] neg bin models with errorsalm and lagsarlm

Hi folks, Is it appropriate to use a negative binomial with errorsalm and lagsarlm? If not is there an alternative to do spatial error and spatial models with a negative binomial? Thanks, Jeff Jeffrey A. Stratford, Ph.D. Postdoctoral Associate 331 Fun

[R-sig-Geo] newbie: Moran's I

Hi. Does anyone have an example of estimating Moran's I from a file with point (not polygon) data? I'm getting close(r) but I still have a few problems. Here's my code so far: library(spdep) ctpoints <- read.csv("c:\\Georgia\\xy.csv", header=TRUE) # only two columns containing the long-lat data

[R-sig-Geo] incorporating spatial autocorrelation (getting started)

Hi. I would like to incorporate spatial autocorreation into some ecological models and I'm overwhelmed by the number of programs out there and I would appreciate some advice where I can get started (and maybe finish!). The study: I surveyed birds along roads every 0.8 km and each point was georef

[R-sig-Geo] newbie: getting started

Greetings! I would appreciate some feedback as to where you think a newbie should start when learning spatial stats with R. I have avian point count data and landscape data (Landsat) over a 70 by 40 km area that I would like to start analyzing. I have already, developed some relationships betw