R/pwr.confIntProp.R
pwr.confIntProp.Rd
This function uses confIntProp()
to compute the required sample size for
estimating a proportion with a given accuracy.
pwr.confIntProp(prop, conf.level = 0.95, w = 0.1, silent = TRUE)
prop | The proportion you expect to find, or a vector of proportions to enable easy sensitivity analyses. |
---|---|
conf.level | The confidence level of the desired confidence interval. |
w | The desired 'halfwidth' of the confidence interval. |
silent | Whether to provide a lot of information about progress ('FALSE') or not ('TRUE'). |
A single numeric value (the sample size).
### Required sample size to estimate a prevalence of .03 in the ### population with a confidence interval of a maximum half-width of .01 pwr.confIntProp(.03, w=.01); #> 0.03 #> 1222 ### Vectorized over prop, so you can easily see how the required sample ### size varies as a function of the proportion pwr.confIntProp(c(.03, .05, .10), w=.01); #> 0.03 0.05 0.1 #> 1222 1926 3556