Spatial statistics

Commands are available form forming variograms and for producing kriged estimates.

forms auto-variograms for individual variates or cross-variograms for pairs of variates

calculates kriged estimates using a model fitted to a sample variogram

forms a covariogram structure containing auto-variograms of individual variates and cross-variograms for pairs from a list of variates

KCROSSVALIDATION

computes cross validation statistics for punctual kriging

MCOVARIOGRAM

fits models to sets of variograms and cross variograms

COKRIGE

calculates kriged estimates using a model fitted to the sample variograms and cross variograms of a set of variates

Procedures in the spatialstatistics module of the Library include:

MVARIOGRAM

fits models to an experimental variogram

LVARMODEL

analyses a field trial using the Linear Variance Neighbour model

DKSTPLOT

produces diagnostic plots for space-time clustering

DPOLYGON

draws polygons using high-resolution graphics

DPTMAP

draws maps for spatial point patterns using high-resolution graphics

DPTREAD

adds points interactively to a spatial point pattern

DRPOLYGON

reads a polygon interactively from the current graphics device

FHAT

calculates an estimate of the F nearest-neighbour distribution function

FZERO

gives the F function expectation under complete spatial randomness

GHAT

calculates an estimate of the G nearest-neighbour distribution function

GRLABEL

randomly labels two or more spatial point patterns

GRTHIN

randomly thins a spatial point pattern

GRTORSHIFT

performs a random toroidal shift on a spatial point pattern

GRCSR

generates completely spatially random points in a polygon

KCSRENVELOPES

simulates K function bounds under complete spatial randomness

KHAT

calculates an estimate of the K function

KLABENVELOPES

gives bounds for K function differences under random labelling

KSED

calculates s.e. for K function differences under random labelling

KSTHAT

calculates an estimate of the K function in space, time and space-time

KSTMCTEST

performs a Monte-Carlo test for space-time interaction

KSTSE

calculates the standard error for the space-time K function

KTORENVELOPES

gives bounds for the bivariate K function under independence

K12HAT

calculates an estimate of the bivariate K function

MSEKERNEL2D

estimates the mean square error for a kernel smoothing

PTAREAPOLYGON

calculates the area of a polygon

PTBOX

generates a box bounding or surrounding a spatial point pattern

PTCLOSEPOLYGON

closes open polygons

PTDESCRIBE

gives summary and second order statistics for a point process

PTGRID

generates a grid of points in a polygon

PTINTENSITY

calculates the overall density for a spatial point pattern

PTKERNEL2D

performs kernel smoothing of a spatial point pattern

PTK3D

performs kernel smoothing of space-time data

PTREMOVE

removes points interactively from a spatial point pattern

PTSINPOLYGON

returns points inside or outside a polygon