CI: Confidence interval of percentages

In pgirmess: Spatial Analysis and Data Mining for Field Ecologists

Confidence interval of percentages

Description

Computes the lower limit and upper limit of the 95 percent confidence interval of percentage estimates

Usage

CI(x, ...)

Arguments

x	a two-dimensional table, matrix or data.frame with 2 columns, giving the counts of successes and failures, respectively
...	other arguments to pass to prop.test, eg conf.level

Details

Simple wrapper of prop.test. The default confidence interval is 95 percent, but can be modified passing values to prop.test by the conf.level argument.

Value

A 3 column matrix.

• Column 1: percentage estimate

• Column 2: lower limit of the confidence interval

• column 3: upper limit of the confidence interval

See Also

prop.test

Examples

x<-c(2,10,7,8,7) # eg: number of positive cases
y<-c(56,22,7,20,5)# eg: number of negative cases
CI(cbind(x,y))
CI(cbind(x,y), conf.level=0.99)

pgirmess documentation built on May 29, 2024, 4:26 a.m.