EVOLUTION-MANAGER
Edit File: autocor.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>R: Spatial autocorrelation</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="R.css" /> </head><body> <table width="100%" summary="page for autocorrelation {raster}"><tr><td>autocorrelation {raster}</td><td style="text-align: right;">R Documentation</td></tr></table> <h2>Spatial autocorrelation</h2> <h3>Description</h3> <p>Compute Moran's I or Geary's C measures of global spatial autocorrelation in a RasterLayer, or compute the the local Moran or Geary index (Anselin, 1995). </p> <h3>Usage</h3> <pre> Geary(x, w=matrix(c(1,1,1,1,0,1,1,1,1), 3,3)) Moran(x, w=matrix(c(1,1,1,1,0,1,1,1,1), 3,3)) MoranLocal(x, w=matrix(c(1,1,1,1,0,1,1,1,1), 3,3)) GearyLocal(x, w=matrix(c(1,1,1,1,0,1,1,1,1), 3,3)) </pre> <h3>Arguments</h3> <table summary="R argblock"> <tr valign="top"><td><code>x</code></td> <td> <p>RasterLayer</p> </td></tr> <tr valign="top"><td><code>w</code></td> <td> <p>Spatial weights defined by or a rectangular matrix with odd length (3, 5, ...) sides (as in <code><a href="focal.html">focal</a></code>) </p> </td></tr> </table> <h3>Details</h3> <p>The default setting uses a 3x3 neighborhood to compute "Queen's case" indices. You can use a filter (weights matrix) to do other things, such as "Rook's case", or different lags. </p> <h3>Value</h3> <p>A single value (Moran's I or Geary's C) or a RasterLayer (Local Moran or Geary values) </p> <h3>Author(s)</h3> <p>Robert J. Hijmans and Babak Naimi</p> <h3>References</h3> <p>Moran, P.A.P., 1950. Notes on continuous stochastic phenomena. Biometrika 37:17-23 </p> <p>Geary, R.C., 1954. The contiguity ratio and statistical mapping. The Incorporated Statistician 5: 115-145 </p> <p>Anselin, L., 1995. Local indicators of spatial association-LISA. Geographical Analysis 27:93-115 </p> <p><a href="http://en.wikipedia.org/wiki/Indicators_of_spatial_association">http://en.wikipedia.org/wiki/Indicators_of_spatial_association</a> </p> <h3>See Also</h3> <p>The spdep package for additional and more general approaches for computing indices of spatial autocorrelation </p> <h3>Examples</h3> <pre> r <- raster(nrows=10, ncols=10) values(r) <- 1:ncell(r) Moran(r) # Rook's case f <- matrix(c(0,1,0,1,0,1,0,1,0), nrow=3) Moran(r, f) Geary(r) x1 <- MoranLocal(r) # Rook's case x2 <- MoranLocal(r, w=f) </pre> <hr /><div style="text-align: center;">[Package <em>raster</em> version 3.3-13 <a href="00Index.html">Index</a>]</div> </body></html>