# seridit: Compute standard error of mean ridit for group given... In ridittools: Useful Functions for Ridit Analysis

## Description

Given a vector of counts for a group and a vector of counts for a reference group, computes the standard error of the mean ridit for the group.

## Usage

 `1` ```seridit(v, ref) ```

## Arguments

 `v` same as `meanridit()`, but must be counts `ref` same as `meanridit()`, but must be counts

## Value

standard error of mean ridit

Eric Bohlman

## References

Fleiss, J.,L., (1981), Statistical Methods for Rates and Proportions. New York: John Wiley & Sons, p. 154

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16``` ```# PolitiFact ratings in order of increasing truthfulness (8 Mar 2018) obama <- c(9, 71, 70, 161, 165, 123) trump <- c(77, 169, 114, 78, 60, 24) # Result is approximately standard normal (meanridit(trump, obama) - 0.5) / seridit(trump, obama) ## The function is currently defined as function (v, ref) { N <- sum(ref) n <- sum(v) term1 <- (n + 1)/N term2 <- 1/(N * (N + n - 1)) term3 <- sum((ref + v)^3)/(N * (N + n) * (N + n - 1)) (1/(2 * sqrt(3 * n))) * sqrt(1 + term1 + term2 - term3) } ```

ridittools documentation built on May 1, 2019, 6:30 p.m.