# moran: Compute Moran's I In spdep: Spatial Dependence: Weighting Schemes, Statistics and Models

## Description

A simple function to compute Moran's I, called by `moran.test` and `moran.mc`;

I = (n sum_i sum_j w_ij (x_i - xbar) (x_j - xbar)) / (S0 sum_i (x_i - xbar)^2)

## Usage

 `1` ```moran(x, listw, n, S0, zero.policy=NULL, 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 NULL, 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 [email protected]

## References

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

`moran.test`, `moran.mc`

## Examples

 ```1 2 3 4 5 6``` ```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)) ```

### Example output

```Loading required package: sp
List of 2
\$ I: num 0.511
\$ K: num 2.23
List of 2
\$ I: num 0.222
\$ K: num 2.77
Warning message:
In lag.listw(listw, z, zero.policy = zero.policy, NAOK = NAOK) :
NAs in lagged values
```

spdep documentation built on Aug. 15, 2018, 5:03 p.m.