size.ci.indirect

Computes the approximate sample size required to estimate a population
standardized indirect effect in a simple mediation model. The direct effect
of the independent (exogenous) variable on the response variable, controlling
for the mediator variable, is assumed to be negligible.

Implements confidence interval and sample size methods that
are especially useful in psychological research. The methods can be
applied in 1-group, 2-group, paired-samples, and multiple-group designs
and to a variety of parameters including means, medians, proportions,
slopes, standardized mean differences, standardized linear contrasts
of means, plus several measures of correlation and association.
Confidence interval and sample size functions are given for single
parameters as well as differences, ratios, and linear contrasts of
parameters. The sample size functions can be used to approximate the
sample size needed to estimate a parameter or function of parameters
with desired confidence interval precision or to perform a variety of
hypothesis tests (directional two-sided, equivalence, superiority,
noninferiority) with desired power. For details see: Statistical Methods
for Psychologists, Volumes 1 – 4, <https://dgbonett.sites.ucsc.edu/>.

Douglas G. Bonett

statpsych

Statistical Methods for Psychologists

Robert J. Calin-Jageman

size.ci.indirect function

<dl><dt>alpha</dt>
<dd>alpha level for 1-alpha confidence</dd>
<dt>cor1</dt>
<dd>planning value of correlation between the independent and mediator variables</dd>
<dt>cor2</dt>
<dd>planning value of correlation between the mediator and response variables</dd>
<dt>w</dt>
<dd>desired confidence interval width</dd></dl>

Arguments

Sample size for an indirect effect confidence interval — size.ci.indirect

<dl>

<dt>alpha</dt>
<dd>alpha level for 1-alpha confidence</dd>


<dt>cor1</dt>
<dd>planning value of correlation between the independent and mediator variables</dd>


<dt>cor2</dt>
<dd>planning value of correlation between the mediator and response variables</dd>


<dt>w</dt>
<dd>desired confidence interval width</dd>

</dl>

size.ci.indirect: Sample size for an indirect effect confidence interval

Description

Usage

Value

Arguments

Examples