LocalMoransI: Local Moran's I

In stevexniu/spots: Spatial Component Analysis

Local Moran's I

Description

Calculate Local Moran's I.

Usage

LocalMoransI(
  X,
  W,
  normalize = TRUE,
  alternative = c("two.sided", "less", "greater"),
  p.adjust.method = "BH",
  scale = TRUE
)

Arguments

X	A matrix with observations as rows and features as columns.
W	A weight matrix across all observations, i.e inverse of a pairwise distance matrix.
normalize	Whether to normalize the weight matrix such that each row adds up to one. Default is TRUE.
alternative	Alternative hypothesis used, default is two.sided.
p.adjust.method	Method used for multiple comparisons correction, default is BH. See p.adjust.
scale	Whether to scale the data. Default is TRUE.

Value

A list containing the following:

• Local.Morans.I, the local Moran's I.

• Z.I, the Z score of local Moran's I.

• X, data matrix used for calculating local Moran's I.

• Y, a matrix of spatial lags.

• Expected.I, the expectation of Moran's I under the null hypothesis.

• SD.I, the standard deviation of Moran's I under the null hypothesis.

• p.val, p-values.

• p.adj, adjusted p-values.

• normalize, whether to normalize the weight matrix.

• scale, whether to scale the data.

• scale.factor, number of observations.

• alternative, alternative hypothesis used.

• p.adjust.method, method used for multiple comparisons correction.

References

Anselin, L. Local indicators of spatial association-LISA. Geogr. Anal. 27, 93–115 (1995) Sokal, R. R., Oden, N. L. & Thomson, B. A. Local spatial autocorrelation in a biological model. Geogr. Anal. 30, 331–354 (1998)

Examples

{
data.use <- quakes[1:100,]
W <- 1/as.matrix(dist(data.use[,1:2]))
diag(W) <- 0
res <- LocalMoransI(data.use[,3:4], W)
}

stevexniu/spots documentation built on July 30, 2022, 9:21 a.m.