cv: Coefficient of variation

In basille/basr: Basic, but hopefully useful, functions

Description

This function computes the coefficient of variation (i.e. sd / mean) of the values in x. If ci is TRUE then confidence intervals are also computed.

Usage

cv(x, na.rm = FALSE, ci = FALSE, conf.level = 0.95,
  method = c("mckaymod", "mckay", "naive"))

Arguments

x	A numeric vector
na.rm	Logical. Should missing values be removed?
ci	Logical. Should confidence intervals be computed?
conf.level	Confidence level of the interval.
method	The method to compute the confidence intervale. Either the naive (naive), the McKay (mckay) or the modified McKay (mckaymod, default) approximation.

Value

If ci, returns a list with the coefficient of variation. in the first element and the confidence interval in the second.

Original URL

http://tolstoy.newcastle.edu.au/R/e2/help/07/06/19043.html

Author(s)

From Kevin Wright, modified by Mathieu Basille [e-mail]

References

Vangel, M. G. (1996) Confidence intervals for a normal coefficient of variation. The American Statistician, 50: 21-26

Examples

xx <- 1:10
cv(xx)
sd(xx)/mean(xx)
cv(xx, ci = TRUE)

basille/basr documentation built on May 11, 2019, 8:32 p.m.