size.test.prop.ps

Computes the sample size required to test a difference in population
proportions with desired power in a paired-samples design. This function
requires planning values for both proportions and a phi coefficient that
describes the correlation between the two dichotomous measurements. The
proportion planning values can be set to .5 for a conservatively large
sample size. The planning value for the effect size (proportion difference)
could be set equal to the difference of the two proportion planning values
or it could be set equal to a minimally interesting effect size. Set the
phi correlation planning value to the smallest value within a plausible range
for a conservatively large sample size.

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.prop.ps function

<dl><dt>alpha</dt>
<dd>alpha level for hypothesis test</dd>
<dt>pow</dt>
<dd>desired power</dd>
<dt>p1</dt>
<dd>planning value of proportion for measurement 1</dd>
<dt>p2</dt>
<dd>planning value of proportion for measurement 2</dd>
<dt>phi</dt>
<dd>planning value of phi correlation</dd>
<dt>es</dt>
<dd>planning value of proportion difference</dd></dl>

Arguments

Sample size for a test of a paired-samples proportion difference — size.test.prop.ps

<dl>

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


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


<dt>p1</dt>
<dd>planning value of proportion for measurement 1</dd>


<dt>p2</dt>
<dd>planning value of proportion for measurement 2</dd>


<dt>phi</dt>
<dd>planning value of phi correlation</dd>


<dt>es</dt>
<dd>planning value of proportion difference</dd>

</dl>

size.test.prop.ps: Sample size for a test of a paired-samples proportion difference

Description

Usage

Value

Arguments

Examples