ci.sigma: Confidence interval for sigma squared.
Description
The function calculates confidence intervals for \(\sigma^2\). We assume that the parent population is normal.
Usage
ci.sigma(data, conf = 0.95, S.sq = NULL, n = NULL, summarized = FALSE)
Arguments
data
A vector of quantitative data. Required if summarized=FALSE.
conf
Level of confidence. 1 - P(type I error).
S.sq
Sample variance, required if summarized=TRUE.
n
Sample size, required if summarized=TRUE.
summarized
Logical. If summarized=TRUE then the user must supply S.sq and n
Value
Returns a list of class = "ci". Default printed results are the point estimate and confidence bounds. Other objects are invisible.
References
Bain, L. J., and M. Engelhardt. 1992. Introduction to Probability and Mathematical
Statistics. Duxbury press. Belmont, CA, USA.
Examples
Run this code# NOT RUN {
ci.sigma(rnorm(20))
# }
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