SpatialPack
Overview

This is the homepage for the R package SpatialPack developed in the Department of Mathematics at Universidad Técnica Federico Santa María, Chile by Felipe Osorio, Ronny Vallejos and Francisco Cuevas.

It provides tools to assess the association between two spatial processes. Currently, three methodologies are implemented: An adapted t-test to perform hypothesis testing about the independence between the processes, a suitable nonparametric correlation coefficient, and the codispersion coefficient.

  1. Tjostheim's Coefficient.
    Tjostheim, D., 1978. A measure of association for spatial variables. Biometrika 65, 109-114.
  2. A Modified Correlation Coefficient Test.
    Clifford, P., Richardson, S., Hémon, D., 1989. Assessing the significance of the correlation between two spatial processes. Biometrics 45, 123-134.
  3. The Codispersion Coefficient.
    Matheron, G., 1965. Les Variables Régionalisées et leur Estimation, Masson, Paris.
    Rukhin, A., Vallejos, R., 2008. Codispersion coefficient for spatial and temporal series. Statistics and Probability Letters 78, 1290-1300.
Features
  • Computes Tjostheim's coefficient and its asymptotic variance for two spatial sequences defined on the same locations on the plane.
  • Performs an hypothesis testing based on a modified version of the correlation coefficient. The test provides a decision rule to elucidate whether the two processes are spatially correlated or not. The spatial sequences need to be defined on the same locations on the plane.
  • Computes de codispersion coefficient for a specific direction h on the plane.
  • Provides a plot for the codispersion coefficient versus the lag distance h for isopropic processes.

Jun 30 2014 SpatialPack