size.test.gen

Computes the sample size required to test a single population parameter with
desired power using a standard error for the parameter estimate from a prior
or pilot study. This function can be used with any type of parameter where the
standard error of the parameter estimate is a function of the square root of the
sample size (most parameter estimates have this property). This function also
assumes that the sampling distribution of the parameter estimate is
approximately normal in large samples.

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.test.gen function

<dl><dt>alpha</dt>
<dd>alpha level for hypothesis test</dd>
<dt>pow</dt>
<dd>desired power</dd>
<dt>se</dt>
<dd>standard error of parameter estimate from prior/pilot study</dd>
<dt>n0</dt>
<dd>sample size of prior/pilot study</dd>
<dt>es</dt>
<dd>planning value of parameter minus null hypothesis value</dd></dl>

Arguments

Sample size for a test of any type of parameter — size.test.gen

<dl>

<dt>alpha</dt>
<dd>alpha level for hypothesis test</dd>


<dt>pow</dt>
<dd>desired power</dd>


<dt>se</dt>
<dd>standard error of parameter estimate from prior/pilot study</dd>


<dt>n0</dt>
<dd>sample size of prior/pilot study</dd>


<dt>es</dt>
<dd>planning value of parameter minus null hypothesis value</dd>

</dl>

size.test.gen: Sample size for a test of any type of parameter

Description

Usage

Value

Arguments

Examples