s.u: Unbiased estimate of the population standard deviation

In MBESS: The MBESS R Package

Unbiased estimate of the population standard deviation

Description

Transforms the usual (and biased) estimate of the standard deviation into an unbiased estimator.

Usage

s.u(s=NULL, N=NULL, X=NULL)

Arguments

s	the usual estimate of the standard deviation (i.e., the square root of the unibased estimate of the variance)
N	sample size s is based
X	vector of scores in which the unbiased estimate of the standard deviation should be calculated

Details

Returns the unbiased estimate for the standard deviation.

Value

The unbiased estimate for the standard deviation.

Author(s)

Ken Kelley (University of Notre Dame; [e-mail])

References

Holtzman, W. H. (1950). The unbiased estimate of the population variance and standard deviation. American Journal of Psychology, 63, 615–617.

Examples

set.seed(113)
X <- rnorm(10, 100, 15)

# Square root of the unbiased estimate of the variance (not unbiased)
var(X)^.5

# One way to implement the function.
s.u(s=var(X)^.5, N=length(X))

# Another way to implement the function.
s.u(X=X)

MBESS documentation built on Oct. 26, 2023, 9:07 a.m.