size.test.mann

Computes the sample size in each group (assuming equal sample sizes)
required for the Mann-Whitney test with desired power. A planning value
of the Mann-Whitney parameter is required. In a 2-group experiment, this
parameter is the proportion of members in the population with scores that
would be larger under treatment 1 than treatment 2. In a 2-group
nonexperiment where participants are sampled from two subpopulations of
sizes N1 and N2, the parameter is the proportion of all N1 x N2 pairs in
which a member from subpopulation 1 has a larger score than a member from
subpopulation 2.

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.mann function

<dl><dt>alpha</dt>
<dd>alpha level for hypothesis test</dd>
<dt>pow</dt>
<dd>desired power</dd>
<dt>p</dt>
<dd>planning value of Mann-Whitney parameter</dd></dl>

Arguments

Sample size for a Mann-Whitney test — size.test.mann

<dl>

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


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


<dt>p</dt>
<dd>planning value of Mann-Whitney parameter</dd>

</dl>

size.test.mann: Sample size for a Mann-Whitney test

Description

Usage

Value

Arguments

References

Examples