# comparebinlinks: Compare two link functions for the binomial distribution In geoBayes: Analysis of Geostatistical Data using Bayes and Empirical Bayes Methods

## Description

Compare two link functions for the binomial distribution.

## Usage

 ```1 2``` ```comparebinlinks(d1, d2, a = -8, b = 8, n = 2001, prob1 = NULL, plot = TRUE) ```

## Arguments

 `d1` Either a positive number or one of "logit" or "probit" defining the link function. If positive number, this corresponds to the `robit(d1)` link. `d2` Same as `d1`. `a` Beginning of range of points to evaluate (and plot) the two link functions. `b` End of range of points to evaluate (and plot) the two link functions. `n` Number of points for evaluating (and plot) the two link functions. `prob1` Binomial probabilities corresponding to the first link function. `plot` Whether the two link functions should be plotted. If so, two plots are created: the left plot shows two curves corresponding to the two link functions (black is the first) and the right plot shows their difference (first - second).

## Details

Finds the closest (after suitable scaling) of the link function `d2` to `d1`. If `prob1` is provided, then this corresponds to probabilities under link `d1` and the probabilities are transformed to `d2`. Also creates a plot of the two link functions.

## Value

A list with the following elements

• `scale` The optimal scaling `c` such that `max(abs(link(x/c,d1) - link(x,d2)))` is minimised for `x = seq(a,b,length.out=n)`

• `maxdiff` The maximum difference between the two links.

• `prob2` The corresponding probabilities from `prob1` to the second link.

## Examples

 ```1 2 3 4 5``` ```## Not run: comparebinlinks("logit", 7) # The robit(7) approximates logit comparebinlinks("probit", 1, prob1 = c(.5, .6, .7, .8, .9)) ## End(Not run) ```

geoBayes documentation built on May 14, 2018, 1:03 a.m.