size.equiv.mean.ps

Computes the sample size required to perform an equivalence test for the
difference in population means with desired power in a paired-samples
design. The value of h specifies a range of practical equivalence, -h to h,
for the difference in population means. The planning value for the absolute
mean difference must be less than h. Equivalence tests often require a
very large sample size. Equivalence tests usually use 2 x alpha rather than
alpha (e.g., use alpha = .10 rather alpha = .05). Set the Pearson correlation
value to the smallest value within a plausible range, and set the variance
planning value to the largest 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.equiv.mean.ps function

<dl><dt>alpha</dt>
<dd>alpha level for hypothesis test</dd>
<dt>pow</dt>
<dd>desired power</dd>
<dt>var</dt>
<dd>planning value of average variance of the two measurements</dd>
<dt>es</dt>
<dd>planning value of mean difference</dd>
<dt>cor</dt>
<dd>planning value of the correlation between measurements</dd>
<dt>h</dt>
<dd>upper limit for range of practical equivalence</dd></dl>

Arguments

Sample size for a paired-samples mean equivalence test — size.equiv.mean.ps

<dl>

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


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


<dt>var</dt>
<dd>planning value of average variance of the two measurements</dd>


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


<dt>cor</dt>
<dd>planning value of the correlation between measurements</dd>


<dt>h</dt>
<dd>upper limit for range of practical equivalence</dd>

</dl>

size.equiv.mean.ps: Sample size for a paired-samples mean equivalence test

Description

Usage

Value

Arguments

Examples