n_2t_equal {dvmisc}

Calculate Per-Group Sample Size for Two-Sample Equal Variance T-Test

Description

Same idea as power.t.test. Less flexible, but faster.

Usage

n_2t_equal(d, sigsq, alpha = 0.05, beta = 0.2)

Arguments

d

Numeric value specifying true difference in group means.

sigsq

Numeric value specifying the variance of observations.

alpha

Numeric value specifying type-1 error rate.

beta

Numeric value specifying type-2 error rate.

Value

Numeric value indicating per-group sample size, rounded up to the nearest whole number.

Examples

# Per-group sample size for 90% power to detect difference of 0.2 with
# sigsq = 1
n_2t_equal(d = 0.2, sigsq = 1, beta = 0.1)