This function uses the MBESS functions conf.limits.ncf()
(which has been
copied into this package to avoid the dependency on MBESS
)
and convert.ncf.to.omegasq()
to compute the point estimate and
confidence interval for Omega Squared (which have been lifted out of MBESS to
avoid importing the whole package)
confIntOmegaSq(var1, var2, conf.level = 0.95)
# S3 method for confIntOmegaSq
print(x, ..., digits = 2)
The two variables: one should be a factor (or will be made a factor), the other should have at least interval level of measurement. If none of the variables is a factor, the function will look for the variable with the least unique values and change it into a factor.
Level of confidence for the confidence interval.
Respectively the object to print, the number of digits to
round to, and any additonal arguments to pass on to the print
function.
A confIntOmegaSq
object is returned, with as elements:
The input arguments
Objects generated while computing the output
The output of the function, consisting of:
The point estimate
The confidence interval
Formula 16 in Steiger (2004) is used for the conversion in
convert.ncf.to.omegasq()
.
Steiger, J. H. (2004). Beyond the F test: Effect size confidence intervals and tests of close fit in the analysis of variance and contrast analysis. Psychological Methods, 9(2), 164-82. https://doi.org/10.1037/1082-989X.9.2.164
confIntOmegaSq(mtcars$mpg, mtcars$cyl);
#> Omega squared: 95% CI = [.51; .81], point estimate = .71