confIntProportion: Confidence interval for binomial proportions

In felix-hof/biostatUZH: Misc Tools of the Department of Biostatistics, EBPI, University of Zurich

Confidence interval for binomial proportions

Description

Compute a confidence interval for binomial proportions using several asymptotic and exact methods.

Usage

confIntProportion(x, n, conf.level = 0.95)

wald(x, n, conf.level = 0.95)

wilson(x, n, conf.level = 0.95)

agresti(x, n, conf.level = 0.95)

jeffreys(x, n, conf.level = 0.95)

clopperPearson(x, n, conf.level = 0.95)

Arguments

x	Number of successes.
n	Total number of trials.
conf.level	Confidence level for confidence interval. Default is 0.95.

Value

confIntProportion returns a data.frame with confidence intervals from the Wald, Wilson, Agresti, Jeffreys, and Clopper-Pearson methods.

wald returns the Wald confidence interval.

wilson returns the Wilson confidence interval.

agresti returns the Agresti confidence interval.

jeffreys returns the Jeffreys confidence interval.

clopperPearson returns the Clopper-Pearson confidence interval.

Author(s)

Kaspar Rufibach, Leonhard Held, Florian Gerber

References

All the intervals provided in these functions are compared in:

Brown, L.D., Cai, T.T., DasGupta, A. (2001). Interval Estimation for a Binomial Proportion. Statistical Science, 16(2), 101–133.

See Also

Functions for some of the intervals provided here are available in Hmisc. confIntIndependentProportion

Examples

## Calculate confidence bounds for a binomial parameter using different methods.
x <- 50
n <- 100
ci <- confIntProportion(x = x, n = n)$CIs
ci

plot(0, 0, type = "n", ylim = c(0, 7), xlim = c(0, 1), xlab = "p",
     ylab = "", yaxt = "n")
for(i in 1:5)
    lines(ci[i, 2:3], c(i, i))
text(0.5, 0.85, "wald")
text(0.5, 1.85, "wilson")
text(0.5, 2.85, "agresti")
text(0.5, 3.85, "jeffreys")
text(0.5, 4.85, "clopper")

## compare intervals to those received by the function binconf in Hmisc:
if (require("Hmisc")) {
    binconf(x, n, method = "asymptotic")   # Wald
    binconf(x, n, method = "wilson")       # Wilson
    binconf(x, n, method = "exact")        # Clopper-Pearson
}

felix-hof/biostatUZH documentation built on Sept. 27, 2024, 1:48 p.m.