docs/prop.is.md

In cwendorf/dgb: DGB

Proportions from Two (Independent) Samples

ci.prop.is

Computes adjusted Wald confidence interval for difference of population proportions in 2-group design.

Arguments: - alpha: alpha level for 1-alpha confidence - f1: number of participants in group 1 with attribute - f2: number of participants in group 2 with attribute - n1: sample size of group 1 - n2: sample size of group 2

Values: - MLEs, SE, lower limit, upper limit

alpha = .05
f1 = 35
f2 = 21
n1 = 150
n2 = 150
ci.prop.is(alpha, f1, f2, n1 ,n2)

##          prop1 prop2         SE          LL        UL
## [1,] 0.2333333  0.14 0.04476077 0.004375769 0.1798348

size.ci.prop.is

Computes sample size per group required to estimate a difference of proportions in 2-group design with desired precision.

Arguments: - alpha: alpha level for 1-alpha confidence - p1: planning value of proportion for group 1 - p2: planning value of proportion for group 2 - w: desired confidence interval width

Values: - required sample size

alpha = .05
p1 = .2
p2 = .4
w = .2
size.ci.prop.is(alpha, p1, p2, w)

## [1] 154

cwendorf/dgb documentation built on May 3, 2022, 9:35 p.m.