mosaic (version 0.5-1)

binom.test: Exact Tests for Proportions

Description

The binom.test function performs an exact test of a simple null hypothesis about the probability of success in a Bernoulli experiment from summarized data or from raw data. The mosaic binom.test provides wrapper functions around the function of the same name in stats. These wrappers provide an extended interface (including formulas).

Usage

binom.test( x, n, p = 0.5, alternative = c("two.sided",
    "less", "greater"), conf.level = 0.95,...)
  ## S3 method for class 'ANY':
binom.test( x, n, p = 0.5, alternative =
    c("two.sided", "less", "greater"), conf.level = 0.95,
    ...)
  ## S3 method for class 'formula':
binom.test( x, n, p = 0.5,
    alternative = c("two.sided", "less", "greater"),
    conf.level = 0.95, success=NULL, data.name, data, ...)
  ## S3 method for class 'numeric':
binom.test( x, n, p = 0.5,
    alternative = c("two.sided", "less", "greater"),
    conf.level = 0.95, success=NULL, data.name, ...)
  ## S3 method for class 'character':
binom.test( x, n, p = 0.5,
    alternative = c("two.sided", "less", "greater"),
    conf.level = 0.95, success=NULL, data.name, ...)
  ## S3 method for class 'logical':
binom.test( x, n, p = 0.5,
    alternative = c("two.sided", "less", "greater"),
    conf.level = 0.95, success=NULL, data.name, ...)
  ## S3 method for class 'factor':
binom.test( x, n, p = 0.5, alternative
    = c("two.sided", "less", "greater"), conf.level = 0.95,
    success=NULL, data.name, ...)

Arguments

x

count of successes, length 2 vector of success and failure counts, a formula, or a character, numeric, or factor vector containing raw data.

n

sample size (successes + failures) or a data frame (for the formula interface)

p

probability for null hypothesis

alternative

type of alternative hypothesis

conf.level

confidence level for confidence interval

success

level of variable to be considered success. All other levels are considered failure.

data.name

name for data. If missing, this is inferred from variable names.

data

a data frame (if missing, n may be a data frame)

...

additional arguments (often ignored)

Value

• an object of class htest

Details

This is a wrapper around binom.test from the base package to simplify its use when the raw data are available, in which case an extended syntax for binom.test is provided.

See Also

prop.test, binom.test

Examples

# Several ways to get a confidence interval for the proportion of Old Faithful
# eruptions lasting more than 3 minutes.
data(faithful)
binom.test(faithful$eruptions > 3)
binom.test(97, 272)
binom.test(c(97, 272-97))
faithful$long <- faithful$eruptions > 3
binom.test(faithful$long)
binom.test(~ long, faithful)