powertools (version 1.0.0)

ttest.1samp: Power calculation for one-sample t test

Description

This function computes power and sample size for a one-sample t test. Can solve for power, N, delta, sd or alpha.

Usage

ttest.1samp(
  N = NULL,
  delta = NULL,
  sd = 1,
  alpha = 0.05,
  power = NULL,
  sides = 2,
  v = FALSE
)

Value

A list of the arguments (including the computed one).

Arguments

N

The sample size.

delta

muA (the true mean) - mu0 (the mean under the null).

sd

The standard deviation; defaults to 1.

alpha

The significance level (type 1 error rate); defaults to 0.05.

power

The specified level of power.

sides

Either 1 or 2 (default) to specify a one- or two-sided hypothesis test.

v

Either TRUE for verbose output or FALSE (default) to output computed argument only.

Examples

ttest.1samp(N = 36, delta = 4.9 - 5.7, sd = 2, sides = 1)
ttest.1samp(N = 36, delta = 6.3 - 5.7, sd = 2, sides = 1)
ttest.1samp(N = 36, delta = 4.9 - 5.7, sd = 2, sides = 2)
ttest.1samp(delta = 0.6, sd = 1, power = 0.8, sides = 1)