R: Variance of a sample estimate for a normal standard deviation...
var.sigma
R Documentation
Variance of a sample estimate for a normal standard deviation
(SD) parameter
Description
Calculates the variance of a sample estimate for a normal SD
parameter.
Usage
var.sigma(s,n)
Arguments
s
A numeric value, the sample standard deviation estimate.
n
A numeric value, the sample size of data.
Details
For a sample dataset of size n drawn from a normal distributin
N(μ,σ^2), denote the sample estimate on
standard deviation (SD) parameter as s. Then the variance of the sample
SD estimate s is Var(s)=0.5*s^2/(n-1).
Value
A numeric value, the variance estimate of the sample estimate for a normal SD parameter.
Note
Bug reports, malfunctioning, or suggestions for further improvements or
contributions can be sent to Jingqin Luo <rosy@wubios.wustl.edu>.
Author(s)
Jingqin Luo
References
Patel, J.K. and Read, C.B. (1996) Handbook of the Normal
Distribution. CRC Press.
Luo, J and Xiong, C. (2012) Youden Index and Associated Optimal Cut-point
for Three Ordinal Groups. Communications In Statistics-Simulation
and Computation (in press).
See Also
var.sigma
Examples
s <- 1.5
n <- 100
var.sigma(s,n)
Results
R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
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Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> library(DiagTest3Grp)
Loading required package: car
Loading required package: KernSmooth
KernSmooth 2.23 loaded
Copyright M. P. Wand 1997-2009
Loading required package: gplots
Attaching package: 'gplots'
The following object is masked from 'package:stats':
lowess
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/DiagTest3Grp/var.sigma.Rd_%03d_medium.png", width=480, height=480)
> ### Name: var.sigma
> ### Title: Variance of a sample estimate for a normal standard deviation
> ### (SD) parameter
> ### Aliases: var.sigma
> ### Keywords: univar htest
>
> ### ** Examples
>
> s <- 1.5
> n <- 100
> var.sigma(s,n)
[1] 0.01136364
>
>
>
>
>
> dev.off()
null device
1
>