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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/tukeySEM.R
\name{tukeySEM}
\alias{tukeySEM}
\title{Tukey's WSD post-hoc test of means for unequal variance and sample size}
\usage{
tukeySEM(m1, m2, var1, var2, n1, n2, ng)
}
\arguments{
\item{m1}{Mean of group 1.}
\item{m2}{Mean of group 2.}
\item{var1}{Variance of group 1.}
\item{var2}{Variance of group 2.}
\item{n1}{Sample size of group 1.}
\item{n2}{Sample size of group 2.}
\item{ng}{Total number of groups to be compared (i.e., the number of groups
compared in the omnibus test).}
}
\value{
A vector with three elements:
\enumerate{
\item \code{q}: The \emph{q} statistic
\item \code{df}: The degrees of freedom for the \emph{q} statistic
\item \code{p}: A \emph{p} value based on the \emph{q} statistic, \emph{df},
and the total number of groups to be compared
}
}
\description{
This function computes Tukey's WSD post hoc test of means when variances and
sample sizes are not equal across groups. It can be used as a post hoc test
when comparing latent means in multiple group SEM.
}
\details{
After conducting an omnibus test of means across three of more groups,
researchers often wish to know which sets of means differ at a particular
Type I error rate. Tukey's WSD test holds the error rate stable across
multiple comparisons of means. This function implements an adaptation of
Tukey's WSD test from Maxwell & Delaney (2004), that allows variances and
sample sizes to differ across groups.
}
\examples{
## For a case where three groups have been compared:
## Group 1: mean = 3.91, var = 0.46, n = 246
## Group 2: mean = 3.96, var = 0.62, n = 465
## Group 3: mean = 2.94, var = 1.07, n = 64
## compare group 1 and group 2
tukeySEM(3.91, 3.96, 0.46, 0.62, 246, 425, 3)
## compare group 1 and group 3
tukeySEM(3.91, 2.94, 0.46, 1.07, 246, 64, 3)
## compare group 2 and group 3
tukeySEM(3.96, 2.94, 0.62, 1.07, 465, 64, 3)
}
\references{
Maxwell, S. E., & Delaney, H. D. (2004). \emph{Designing
experiments and analyzing data: A model comparison perspective} (2nd ed.).
Mahwah, NJ: Lawrence Erlbaum Associates.
}
\author{
Alexander M. Schoemann (East Carolina University;
\email{schoemanna@ecu.edu})
}
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