cloglog.sample.size {binom}

Power and sample size

Description

Power and sample size for a binomial proportion using the cloglog parameterization.

Usage

cloglog.sample.size(p.alt, n = NULL, p = 0.5, power = 0.8, alpha = 0.05,
                    alternative = c("two.sided", "greater", "less"), exact.n = FALSE,
                    recompute.power = FALSE, phi = 1)

Arguments

p.alt

The alternative proportion in a one-sample test.

n

The sample size in a one-sample test.

p

The null proportion in a one-sample test. Default is 0.5.

power

The desired power level. Default is 0.80.

alpha

The desired alpha level - probability of a Type I error. Default is 0.05.

alternative

Nature of alternative hypothesis. One of "two.sided", "greater", "less".

exact.n

logical; If TRUE, the computed sample size will not be rounded up. Default is FALSE.

recompute.power

logical; If TRUE, after the sample size is computed, the power will be recomputed. This is only advantageous when the sample size is rounded up. Default is FALSE.

phi

Dispersion parameter by which to inflate (phi > 1) or deflate (phi < 1) variance. Default is 1.

Details

This function can be used to calculate sample size, power or minimum detectable difference. It determines what to compute base on the arguments provided. If p.alt is given, but n is not, then sample size is computed. If p.alt is given along with n, then the power is computed. If only n is provided, the minimum detectable difference is computed using the default power of 0.80.

Value

A data.frame containing the power, sample size and all of the input which was used to perform the computations.

Author(s)

Sundar Dorai-Raj ([e-mail])

See Also

binom.confint

Examples

cloglog.sample.size(p.alt = 0.8)
cloglog.sample.size(n = 20)
cloglog.sample.size(n = 20, power = 0.9)