moran.Rd
A simple function to compute Moran's I, called by moran.test
and moran.mc
;
$$I = \frac{n}{\sum_{i=1}^{n}\sum_{j=1}^{n}w_{ij}}
\frac{\sum_{i=1}^{n}\sum_{j=1}^{n}w_{ij}(x_i-\bar{x})(x_j-\bar{x})}{\sum_{i=1}^{n}(x_i - \bar{x})^2}
$$
moran(x, listw, n, S0, zero.policy=NULL, NAOK=FALSE)
a numeric vector the same length as the neighbours list in listw
a listw
object created for example by nb2listw
number of zones
global sum of weights
default NULL, use global option value; if TRUE assign zero to the lagged value of zones without neighbours, if FALSE assign NA
if 'TRUE' then any 'NA' or 'NaN' or 'Inf' values in x are passed on to the foreign function. If 'FALSE', the presence of 'NA' or 'NaN' or 'Inf' values is regarded as an error.
a list of
Moran's I
sample kurtosis of x
Cliff, A. D., Ord, J. K. 1981 Spatial processes, Pion, p. 17.
data(oldcol)
col.W <- nb2listw(COL.nb, style="W")
crime <- COL.OLD$CRIME
str(moran(crime, col.W, length(COL.nb), Szero(col.W)))
#> List of 2
#> $ I: num 0.511
#> $ K: num 2.23
is.na(crime) <- sample(1:length(crime), 10)
str(moran(crime, col.W, length(COL.nb), Szero(col.W), NAOK=TRUE))
#> Warning: NAs in lagged values
#> List of 2
#> $ I: num 0.142
#> $ K: num 2.82