z.score {corpora} R Documentation

## The z-score statistic for frequency counts (corpora)

### Description

This function computes a z-score statistic for frequency counts, based on a normal approximation to the correct binomial distribution under the random sampling model.

### Usage


z.score(k, n, p = 0.5, correct = TRUE)



### 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)

### Details

The z statistic is given by

% z := \frac{k - np}{\sqrt{n p (1-p)}} 

When Yates' continuity correction is enabled, the absolute value of the numerator d := k - np is reduced by 1/2, but clamped to a non-negative value.

### Value

The z-score corresponding to the specified data (or a vector of z-scores).

### Author(s)

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

### See Also

z.score.pval

[Package corpora version 0.5-1 Index]