power.z.test {asbio}R Documentation

Power analysis for a one sample z-test

Description

A power analysis for a one sample z-test. The function requires alpha, sigma, the effect size, the type of test (one tailed or two-tailed), and either power (1 - beta) or n (sample size). If n is provided, then power is calculated. Conversely, if one provides power, but not n, then n is calculated.

Usage


power.z.test(sigma = 1, n = NULL, power = NULL, alpha = 0.05, effect = NULL, test = c("two.tail", "one.tail"))

Arguments

sigma The population variance
n The sample size. Not required if power is specified.
power The desired power. Not required if n is specified.
alpha Probability of type I error.
effect Effect size.
test One of two choices: "two.tail" or "one.tail".

Value

Returns a list

sigma The prescribed population variance.
n The sample size.
power The power.
alpha The type I error probability.
test The type of test prescribed.
effect The effect size.

Author(s)

Ken Aho

References

Bain, L. J., and M. Engelhardt (1992) Introduction to probability and mathematical statistics. Duxbury press. Belmont, CA, USA.

See Also

pnorm

Examples

power.z.test(sigma=6,effect=5,power=.9,test="one.tail")

[Package asbio version 0.1 Index]