Correlogram

Calculates and plots a correlogram

correlogram(x, v, dist = 5000, dmatrix = FALSE, ns = 99, latlong = FALSE, ...)

Arguments

x	SpatialPointsDataFrame object
v	Test variable in x@data
dist	Distance of correlation lags, if latlong=TRUE units are in kilometers
dmatrix	Should the distance matrix be include in output (TRUE/FALSE)
ns	Number of simulations to derive simulation envelope
latlong	Coordinates are in latlong (TRUE/FALSE)
...	Arguments passed to cor ('pearson', 'kendall' or 'spearman')

Value

A list object containing:

• autocorrelation is a data.frame object with the following components

• autocorrelation - Autocorrelation value for each distance lag

• dist - Value of distance lag

• lci - Lower confidence interval (p=0.025)

• uci - Upper confidence interval (p=0.975)

• CorrPlot recordedplot object to recall plot

• dmatrix Distance matrix (if dmatrix=TRUE)

Author

Jeffrey S. Evans jeffrey_evans@tnc.org

Examples

library(sp)
  data(meuse)
coordinates(meuse) = ~x+y
zinc.cg <- correlogram(x = meuse, v = meuse@data[,'zinc'], dist = 250, ns = 9)