size.ci.pbcor

Computes the sample size required to estimate a population point-biserial
correlation with desired confidence interval precision in a two-group
nonexperimental design with simple random sampling. A two-group
nonexperimental design implies two subpopulations (e.g., all boys and all
girls in a school district). This function requires a planning value for the
proportion of population members who belong to one of the two subpopulations.
Set the correlation planning value to the smallest absolute value within a
plausible range for a conservatively large sample size.
For more details, see Section 1.24 of Bonett (2021, Volume 2)

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.pbcor function

<dl><dt>alpha</dt>
<dd>alpha level for 1-alpha confidence</dd>
<dt>cor</dt>
<dd>planning value of point-biserial correlation</dd>
<dt>w</dt>
<dd>desired confidence interval width</dd>
<dt>p</dt>
<dd>proportion of members in one of the two subpopulations</dd></dl>

Arguments

Sample size for a point-biserial correlation confidence interval — size.ci.pbcor

<dl>

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


<dt>cor</dt>
<dd>planning value of point-biserial correlation</dd>


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


<dt>p</dt>
<dd>proportion of members in one of the two subpopulations</dd>

</dl>

size.ci.pbcor: Sample size for a point-biserial correlation confidence interval

Description

Usage

Value

Arguments

References

Examples