Hi,

 

I need to create a weight matrix in R  for point dataset of 78,000
observations from a shapefile( from ArcGIS) which has both sets of
longitudes and latitudes and X-Y coordinates (based on state plane feet).  

So far I projected the dataset in ESRI coordinates using rgdal maptools. 

I  keep getting error message as below:

 

shapeR_SP <-spTransform(shapeR, CRS("+init=ESRI:102730"))

> IDs <-row.names(as(shapeR_SP, "data.frame"))

> coords<-coordinates(shapeR_SP)

> shapeR_nbq <-poly2nb(shapeR_SP)

Error: extends(class(pl), "SpatialPolygons") is not TRUE

> shapeR_kn6 <-knn2nb(knearneigh(coords, k=6), row.names=IDs)

Warning message:

In library(package, lib.loc = lib.loc, character.only = TRUE, logical.return
= TRUE,  :

  there is no package called 'RANN'

 

where is 'RANN' from?!

 

The outcome goal is to address the spatial dependence  in hedonic model with
house sales transaction study.  I like to run the spatial dependence test so
that I can refine the spatial regession analysis.

 

I would appreciate any suggestions  and/or  answers to the following
questions:

1.       What is the sample size capacity of R (weight matrix size)?  This
is the main reason I switched back to R from Stata.  Is there any means to
achieve the outcomes I am looking for?

2.       Do I need to install.view ("Spatial)? When I tried to
install.view("Spatial"), I've been getting a message that that package is
not available for R 3.0 which I am using - R studio. Is "Spatial" different
from "spatial" package?  Do I need to find a different version of R?

3.       Is there a better to achieve the outcome?  For instance, using
GeoDa to create a weight matrix?  

 

Thank you.  

 

Susan Shim Gorelick

 


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