fitPS (version 1.0.1)

compareSurveysLRT: Compare two or more surveys on the basis of their shape parameters using a Likelihood Ratio Test

Description

Compare two or more surveys on the basis of their shape parameters using a Likelihood Ratio Test

Usage

compareSurveysLRT(...)

Value

The function returns a list of class "htest" with the following elements:

statistic

-- the test statistic.

parameter

-- the degrees of freedom for the test

p.value

-- the P-value associated with the estimate.

method

-- a character string describing the method hypothesis.

data.name

-- the names of the data sets used in the test

Arguments

...

two or more objects of class "psData"---see readData.

Details

This function **only** works for the zeta distribution. The function carries out a likelihood ratio test (LRT) to test the null hypothesis $$H_0: \alpha_1 = \alpha_2 = \ldots = \alpha_K$$ versus the alternative $$H_1: \alpha_i \neq \alpha_j \mbox{ for some } i \neq j \in \left\{1, \ldots, K\right\},$$ where \(\alpha_i\) is the shape parameter for the zeta distribution of the \(i^\mathrm{th}\) survey.

Examples

data(Psurveys)
lau = Psurveys$lau
jackson = Psurveys$jackson
compareSurveysLRT(lau, jackson)

## Example with three surveys
roux = Psurveys$roux
compareSurveysLRT(lau, jackson, roux)