z_B1._Testing_surface_: Testing the surface model

In scpm: An R Package for Spatial Smoothing

Description

Test the model for the surface of response. The null hypothesis is assumed as a linear model defined by the coordinates while the alternative hypothesis is assumed a bivariate spline (tensor product or thin-plate spline).

Usage

## S4 method for signature 'sssFit'
testSurface(object, tol)

Arguments

object	an object of class sssFit from command scp.
tol	numeric. Numeric tolerance to use for some inversion of matrices. Default to .Machine$double.neg.eps*1.0e-10.

Details

If we have defined a bivariate spline using s2D in the formula of scp then the model is an spatial semiparametric model based on splines (tensor products or thin-plate splines). In this case testSurface performs a test for the null hypothesis H_0: g = Xβ (linear model) against the alternative H_1: g = Xβ + Zr (spline model). When g is assumed as a thin-plate spline then this test is equivalent to test the null hypothesis H_0: the pattern of response in the space is a plane against the alternative H_1: the pattern of response in the space is a bivariate thin-plate spline. In one dimension this test is equivalent to a test for linearity in the pattern of response.

Value

Returns a table with the degrees of freedom, sum of squares and mean squares from different sources and the F test and its associated p-value.

Author(s)

Mario A. Martinez Araya, [e-mail]

scpm documentation built on Feb. 17, 2020, 5:08 p.m.