size.ci.lc.mean.ws

Computes the sample size required to estimate a linear contrast of
population means with desired confidence interval precision in a
within-subjects design. Set the variance planning value to the
largest value within a plausible range for a conservatively large
sample size. Set the Pearson correlation planning value to the
smallest value within a plausible range for a conservatively
large sample size.
For more details, see Section 4.26 of Bonett (2021, Volume 1)

Implements confidence interval and sample size methods that are especially
useful in psychological research but are also useful in educational, social science,
business, and biological research. This package includes more than 100 confidence
interval functions and more than 80 sample size functions for 1-group, 2-group,
paired-samples, and multiple-group designs and for a variety of parameters including
means, medians, proportions, slopes, standardized mean differences, standardized
linear contrasts of means, and several measures of correlation and association. 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 about these methods 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.lc.mean.ws function

<dl><dt>alpha</dt>
<dd>alpha level for 1-alpha confidence</dd>
<dt>var</dt>
<dd>planning value of average variance of the measurements</dd>
<dt>cor</dt>
<dd>planning value of average correlation between measurements</dd>
<dt>w</dt>
<dd>desired confidence interval width</dd>
<dt>q</dt>
<dd>vector of within-subjects contrast coefficients</dd></dl>

Arguments

Sample size for a within-subjects mean linear contrast confidence interval — size.ci.lc.mean.ws

<dl>

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


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


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


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


<dt>q</dt>
<dd>vector of within-subjects contrast coefficients</dd>

</dl>

size.ci.lc.mean.ws: Sample size for a within-subjects mean linear contrast confidence interval

Description

Usage

Value

Arguments

References

Examples