z.score.pval {corpora}

P-values of the z-score test for frequency counts (corpora)

Description

This function computes the p-value of a z-score test for frequency counts, based on the z-score statistic implemented by z.score.

Usage

z.score.pval(k, n, p = 0.5, correct = TRUE,
             alternative = c("two.sided", "less", "greater"))

Arguments

k

frequency of a type in the corpus (or an integer vector of frequencies)

n

number of tokens in the corpus, i.e. sample size (or an integer vector specifying the sizes of different samples)

p

null hypothesis, giving the assumed proportion of this type in the population (or a vector of proportions for different types and/or different populations)

correct

if TRUE, apply Yates' continuity correction (default)

alternative

a character string specifying the alternative hypothesis; must be one of two.sided (default), less or greater

Value

The p-value of a z-score test applied to the given data (or a vector of p-values).

Author(s)

Stephanie Evert (https://purl.org/stephanie.evert)

See Also

z.score, binom.pval, prop.cint

Examples

# compare z-test for H0: pi = 0.15 against binomial test
# with observed counts 10..30 in a sample of n=100 tokens
k <- c(10:30)
p.compare <- rbind(
  z.score = z.score.pval(k, 100, p=.15),
  binomial = binom.pval(k, 100, p=.15))
colnames(p.compare) <- k
round(p.compare, 4)