| ci.prop {statpsych} | R Documentation |
Confidence intervals for a proportion
Description
Computes adjusted Wald and Wilson confidence intervals for a population proportion. The Wilson confidence interval uses a continuity correction.
ci.prop1 is deprecated and will soon be removed from statpsych; please switch to ci.prop
Usage
ci.prop(alpha, f, n)
ci.prop1(alpha, f, n)
Arguments
alpha |
alpha level for 1-alpha confidence |
f |
number of participants who have the attribute |
n |
sample size |
Value
Returns a 2-row matrix. The columns of row 1 are:
Estimate - adjusted estimate of proportion
SE - adjusted standard error
LL - lower limit of the adjusted Wald confidence interval
UL - upper limit of the adjusted Wald confidence interval
The columns of row 2 are:
Estimate - ML estimate of proportion
SE - standard error
LL - lower limit of the Wilson confidence interval
UL - upper limit of the Wilson confidence interval
References
Agresti A, Coull BA (1998). “Approximate is better than 'exact' for interval estimation of binomial proportions.” The American Statistician, 52(2), 119–126. ISSN 0003-1305, doi:10.1080/00031305.1998.10480550.
Examples
ci.prop(.05, 12, 100)
# Should return:
# Estimate SE LL UL
# Adjusted Wald 0.1346154 0.03346842 0.06901848 0.2002123
# Wilson with cc 0.1200000 0.03249615 0.06625153 0.2039772