nProp2sam: Simple random sample size for difference in proportions

In PracTools: Tools for Designing and Weighting Survey Samples

Simple random sample size for difference in proportions

Description

Compute a simple random sample size for estimating the difference in proportions when samples overlap

Usage

nProp2sam(px, py, pxy, g, r, alt, sig.level=0.05, pow=0.80)

Arguments

px	proportion in group 1
py	proportion in group 2
pxy	proportion in the overlap has the characteristic in both samples
g	proportion of sample 1 that is in the overlap with sample 2
r	ratio of the size of sample 1 to that of sample 2
alt	should the test be 1-sided or 2-sided; allowable values are alt="one.sided" or alt="two.sided".
sig.level	significance level of the hypothesis test
pow	desired power of the test

Details

nProp2sam computes sample sizes in two groups that are required for testing whether the difference in group proportions is significant. The power of the test is one of the input parameters. The samples have a specified proportion of units in common.

Value

List with values:

n1	sample size in group 1
n2	sample size in group 2
px.py.pxy	input values of the px, py, pxy parameters
gamma	proportion of sample 1 that is in the overlap with sample 2
r	ratio of the size of sample 1 to that of sample 2
alt	type of test: one-sided or two-sided
sig.level	significance level of test
power	power of the test

Author(s)

Richard Valliant, Jill A. Dever, Frauke Kreuter

References

Valliant, R., Dever, J., Kreuter, F. (2018, chap. 4). Practical Tools for Designing and Weighting Survey Samples, 2nd edition. New York: Springer.

Woodward, M. (1992). Formulas for Sample Size, Power, and Minimum Detectable Relative Risk in Medical Studies. The Statistician, 41, 185-196.

See Also

nDep2sam

Examples

nProp2sam(px=0.5, py=0.55, pxy=0.45, g=0.5, r=1, alt="two.sided")

PracTools documentation built on Nov. 9, 2023, 9:06 a.m.