iccmult
Intracluster Correlation Coefficient (ICC) in Clustered Categorical Data
Assists in generating categorical clustered outcome data, estimating the Intracluster Correlation Coefficient (ICC) for nominal or ordinal data with 2+ categories under the resampling and method of moments (MoM) methods, with confidence intervals.
iccmult
The goal of iccmult is to estimate the intracluster correlation
coefficient (ICC) of clustered categorical response data. It provides
two estimation methods, a resampling based estimator and the method of
moments estimator. These are obtained by specifying a method in the
function iccmulti::iccmult(). This package also includes a function to
generate simulated clustered categorical response data:
iccmulti::rccat().
Installation
You can install iccmult from within R or RStudio with:
install.packages("iccmult")
Alternatively, install the package from GitHub with:
# install.packages("pak")
pak::pak("ncs14/iccmult")
Example
This is a basic example which shows you how to generate clustered
categorical response data. The response probabilities must sum 1 and the
desired ICC must be a value between 0 and 1. The number of clusters is
set to 20 and each cluster is of size 25. The output of rccat is a two
column data frame of a cluster identifier and a categorical response
vector.
library(iccmult)
clustdat3 <- rccat(rho=0.25, prop=c(0.2,0.3,0.5), noc=20, csize=25)
The iccmulti() function is called as follows to estimate the ICC on
the resulting data frame. The function expects two variables: a cluster
identifier and the categorical response vector. The call below requests
both the resampling and the moments estimates.
iccclust <- iccmulti(cid, y, clustdat3, method=c("rm","mom"))
#> Warning in iccmulti(cid, y, clustdat3, method = c("rm", "mom")): ICC not
#> estimable by 'Resampling' method for at least one categorical calculation
#> Warning in iccmulti(cid, y, clustdat3, method = c("rm", "mom")): Resampling
#> based confidence interval for ICC is not estimable for at least one categorical
#> calculation
#> Warning in iccmulti(cid, y, clustdat3, method = c("rm", "mom")): Resampling
#> based confidence interval for categorical ICC is not estimable
#> Warning in iccmulti(cid, y, clustdat3, method = c("rm", "mom")): Categorical
#> ICC not estimable by 'Resampling' method
The result is a list of length two, each component holding the estimated ICC, se(ICC), and confidence interval bounds from each estimation method.