spherical.gc: The Spherical Correlation Function of Class 'corr.gc'

In gcKrig: Analysis of Geostatistical Count Data using Gaussian Copulas

The Spherical Correlation Function of Class corr.gc

Description

The spherical correlation function in spatial statistics.

By default, range parameter is not available, so this function is used for likelihood inference and spatial prediction in function mlegc and predgc. Users need to specify if the correlation model includes a nugget effect nugget = TRUE or not nugget = FALSE.

When both range and nugget parameters are given, the function is used for simulation with function simgc in package gcKrig.

Usage

spherical.gc(range = NULL, nugget = TRUE)

Arguments

range	a non-negative scalar of the range parameter in the spherical correlation function.
nugget	the nugget effect of the correlation function. If specified, it must be a scalar between 0 and 1.

Details

The spherical correlation function with a nugget τ^2 is of the form:

ρ(h) = (1-τ^2) (1 - 1.5(h/φ) + 0.5(-h/φ)^3)

when h > 0 and ρ(h) = 1 when h = 0, h is distance.

Value

An object of class corr.gc representing the correlation component.

Author(s)

Zifei Han [e-mail]

See Also

matern.gc, spherical.gc

gcKrig documentation built on July 3, 2022, 1:05 a.m.