| ci.prop.inv {statpsych} | R Documentation |
Confidence interval for a proportion using inverse sampling
Description
Computes an exact confidence interval for a population proportion when inverse sampling has been used. An approximate standard error is recovered from the confidence interval. With inverse sampling, the number of participants who have the attribute (f) is predetermined and sampling continues until f attains its prespecified value. With inverse sampling, the sample size (n) will not be known in advance.
Usage
ci.prop.inv(alpha, f, n)
Arguments
alpha |
alpha level for 1-alpha confidence |
f |
number of participants who have the attribute (fixed) |
n |
sample size (random) |
Value
Returns a 1-row matrix. The columns are:
Estimate - estimate of proportion
SE - recovered standard error
LL - lower limit of confidence interval
UL - upper limit of confidence interval
References
Zou GY (2010). “Confidence interval estimation under inverse sampling.” Computational Statistics & Data Analysis, 54(1), 55–64. ISSN 0167-9473, doi:10.1016/j.csda.2005.05.007.
Examples
ci.prop.inv(.05, 5, 67)
# Should return:
# Estimate SE LL UL
# 0.07462687 0.03145284 0.02467471 0.1479676