moran: Compute Moran's I
In r-spatial/spdep: Spatial Dependence: Weighting Schemes, Statistics

moran

R Documentation

Compute Moran's I

Description

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}

Usage

moran(x, listw, n, S0, zero.policy=attr(listw, "zero.policy"), NAOK=FALSE)

Arguments

`x`	a numeric vector the same length as the neighbours list in listw
`listw`	a `listw` object created for example by `nb2listw`
`n`	number of zones
`S0`	global sum of weights
`zero.policy`	default `attr(listw, "zero.policy")` as set when `listw` was created, if attribute not set, use global option value; if TRUE assign zero to the lagged value of zones without neighbours, if FALSE assign NA
`NAOK`	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.

Value

a list of

`I`	Moran's I
`K`	sample kurtosis of x

Author(s)

Roger Bivand Roger.Bivand@nhh.no

References

Cliff, A. D., Ord, J. K. 1981 Spatial processes, Pion, p. 17.

Examples

data(oldcol)
col.W <- nb2listw(COL.nb, style="W")
crime <- COL.OLD$CRIME
str(moran(crime, col.W, length(COL.nb), Szero(col.W)))
is.na(crime) <- sample(1:length(crime), 10)
str(moran(crime, col.W, length(COL.nb), Szero(col.W), NAOK=TRUE))

r-spatial/spdep documentation built on Dec. 3, 2024, 3:27 a.m.