power_best_binomial: Power to Correctly Select the Best Group in a Binomial Test

In ssutil: Sample Size Calculation Tools

Power to Correctly Select the Best Group in a Binomial Test

Description

Computes the exact probability of correctly identifying the best group when the outcome follows a binomial distribution. It assumes that p1 is the probability of success in the best group, and that the success probability in all other groups is lower by a fixed difference dif.

Usage

power_best_binomial(p1, dif, ngroups, npergroup)

Arguments

p1	Numeric. Probability of success in the best group (must be in [0, 1]).
dif	Numeric. Difference in success probability between the best group and the next best (must be > 0).
ngroups	Integer. Number of groups (must be greater than 1).
npergroup	Integer. Number of subjects per group (must be positive).

Details

The formula is based on the exact method described by Sobel and Huyett (1957).

Value

A numeric value representing the probability of correctly identifying the best group.

References

Sobel, M., & Huyett, M. J. (1957). Selecting the Best One of Several Binomial Populations. Bell System Technical Journal, 36(2), 537–576. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.1002/j.1538-7305.1957.tb02411.x")}

Examples

power_best_binomial(p1 = 0.8, dif = 0.2, ngroups = 4, npergroup = 50)

ssutil documentation built on Sept. 18, 2026, 1:06 a.m.