lrt: Likelihood Ratio Test

Description Usage Arguments Details Value Examples

View source: R/lrt.R

Description

A function to perform a likelihood ratio test for testing two nested models against each other.

Usage

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lrt(fit1, fit2)

Arguments

fit1

a fitted model object of class mumm.

fit2

a fitted model object of class mumm, lm or merMod.

Details

Performs the likelihood ratio test for testing two nested models against each other. The model in fit2 should be nested within the model in fit1.

Value

A matrix with the likelihood ratio test statistic and the corresponding p-value.

Examples

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set.seed(100)
sigma_e <- 1.5
sigma_a <- 0.8
sigma_b <- 0.5
sigma_d <- 0.7
nu <- c(8.2, 6.2, 2.3, 10.4, 7.5, 1.9)

nA <- 15
nP <- 6
nR <- 5

a <- rnorm(nA, mean = 0, sd = sigma_a)
b <- rnorm(nA, mean = 0, sd = sigma_b)
d <- rnorm(nA*nP, mean = 0, sd = sigma_d)
e <- rnorm(nA*nP*nR, mean = 0, sd = sigma_e)

Assessor <- factor(rep(seq(1,nA),each = (nP*nR)))
Product <- factor(rep(rep(seq(1,nP),each = nR), nA))
AssessorProduct <- (Assessor:Product)

y <- nu[Product] + a[Assessor] + b[Assessor]*(nu[Product]-mean(nu)) + d[AssessorProduct] + e

sim_data <- data.frame(y, Assessor, Product)

fit <- mumm(y ~ 1 + Product + (1|Assessor) + (1|Assessor:Product) +
             mp(Assessor,Product) ,data = sim_data)

fit2 <- mumm(y ~ 1 + Product + (1|Assessor) + mp(Assessor,Product) ,data = sim_data)
lrt(fit,fit2)

sofpj/mumm documentation built on May 30, 2019, 6:08 a.m.