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[localmoran.exact]

2 messages · Lisa Menez, Roger Bivand

Lisa Menez
# 
Dear all, 

I have been trying to obtain local Moran?s I with the exact approach (localmoran.exact)
 but I have some issues and would need your help. 

I am trying to bring to light how spatial patterns of wealth have evolved from 2000 to 2016 in the European Union. 

Looking at the Regional Gross Domestic Product (GDP) of European regions, my lm model looks like this : 

lm(log(EU_NUTS at data[,year[i]])~1+factor(EU_NUTS at data$NUTS_L1))

where log(EU_NUTS at data[,year[i]]) are log of regional GDPs

and factor(EU_NUTS at data$NUTS_L1) is the vector of country dummies.

Sadly, I obtain an error message that says : 

Error in integrate(integrand, lower = 0, upper = upper) : 
  a limit is missing
Moreover : Warning messages:
1: In sqrt(2 * t2 - t1^2) : production of NaN
2: In sqrt(2 * t2 - t1^2) : production of NaN 

According to the GitHub source code , 

        Vi <- listw2star <https://rdrr.io/cran/spdep/man/localmoran.sad.html>(B, select[i], style=style, n, D <https://rdrr.io/r/stats/deriv.html>, a,
	    zero.policy=zero.policy)
        Viu <- lag.listw <https://rdrr.io/cran/spdep/man/lag.listw.html>(Vi, u, zero.policy=TRUE <https://rdrr.io/r/base/logical.html>)
	Ii <- c <https://rdrr.io/r/base/c.html>(crossprod <https://rdrr.io/r/base/crossprod.html>(u, Viu) / utu)
        ViX <- lag.listw <https://rdrr.io/cran/spdep/man/lag.listw.html>(Vi, X, zero.policy=TRUE <https://rdrr.io/r/base/logical.html>)
        MViM <- t <https://rdrr.io/r/base/t.html>(X) %*% ViX %*% XtXinv
        t1 <- -sum <https://rdrr.io/r/base/sum.html>(diag <https://rdrr.io/r/base/diag.html>(MViM))
        sumsq.Vi <- function <https://rdrr.io/r/base/function.html>(x) {
            if <https://rdrr.io/r/base/Control.html> (is.null <https://rdrr.io/r/base/NULL.html>(x)) NA <https://rdrr.io/r/base/NA.html>
	    else <https://rdrr.io/r/base/Control.html> sum <https://rdrr.io/r/base/sum.html>(x^2)
	}
	trVi2 <- sum <https://rdrr.io/r/base/sum.html>(sapply <https://rdrr.io/r/base/lapply.html>(Vi$weights <https://rdrr.io/r/stats/weights.html>, sumsq.Vi), na.rm=TRUE <https://rdrr.io/r/base/logical.html>)
	t2a <- sum <https://rdrr.io/r/base/sum.html>(diag <https://rdrr.io/r/base/diag.html>(t <https://rdrr.io/r/base/t.html>(ViX) %*% ViX %*% XtXinv))
	t2b <- sum <https://rdrr.io/r/base/sum.html>(diag <https://rdrr.io/r/base/diag.html>(MViM %*% MViM))
	t2 <- trVi2 - 2*t2a + t2b
	e1 <- 0.5 * (t1 + sqrt <https://rdrr.io/r/base/MathFun.html>(2*t2 - t1^2))
	en <- 0.5 * (t1 - sqrt <https://rdrr.io/r/base/MathFun.html>(2*t2 - t1^2))

My guess is that my setting causes (2*t2<t1^2) : Is it ? Why would it ? 

My database is available here : http://hcc.cnrs.fr/wp-content/uploads/2018/08/mydata2018-1.txt <http://hcc.cnrs.fr/wp-content/uploads/2018/08/mydata2018-1.txt>
and my code : http://hcc.cnrs.fr/wp-content/uploads/2018/08/myCode_2018.txt <http://hcc.cnrs.fr/wp-content/uploads/2018/08/myCode_2018.txt>

I thank you very much for your attention and your help. 

Best Regards
Lisa 

PhD Student
GREDEG, Universit? C?t? d?Azur
Roger Bivand
#
On Mon, 13 Aug 2018, Lisa Menez wrote:

            

      
      
      
    

        
A complete reproducible example is required (script and data, data may be 
downloaded, do not attach). Does the same thing happen with 
localmoran.sad()?

            

      
      
      
    

        
Never, ever use @ to access data. EU_NUTS at data$NUTS_L1 should be 
EU_NUTS$NUTS_L1 and should be (made a) factor first. It isn't clear what 
log(EU_NUTS at data[,year[i]]) will end up being - is "year" a character 
vector? If so, EU_NUTS[[year[i]]] is the correct syntax.

            

      
      
      
    

        
No, as you can see from https://cran.r-project.org/package=spdep, the 
development site of spdep is https://github.com/r-spatial/spdep/. Never 
use non-authorised copies. To see the source, simply type the function 
name. Use debug(localmoran.exact) to step through the function while it 
runs, to see the values of the objects you are in doubt about. Do not do 
this in RStudio, its debugging interface tries to be far too clever.

The following is illegible in plain text; post in plain text only.

Roger