ptmean {cdfinv} | R Documentation |
Cumulative distribution function for t distribution
Description
Computes the quantile of the t distribution for n-1 degrees of freedom corresponding to the input value of the sample mean.
Usage
ptmean(q, mean, s2, n)
Arguments
q |
coordinate at which the cdf is to be evaluated (named in accordance with R standards) |
mean |
the assumed normal mean |
s2 |
the observed sample variance (pass this as an extra argument to cdfinv()) |
n |
the sample size (pass this as an extra argument to cdfinv()) |
Details
Do not call ptmean() directly. Pass DISTR="tmean" to cdfinv() when computing intervals for the normal mean when the variance is unknown. The parameter name to be passed to cdfinv() is mean. The additional arguments s2 (sample variance) and n (sample size) are to be passed to cdfinv().
Value
The quantile of the t distribution for n-1 degrees of freedom corresponding to the input value of the sample mean.
Author(s)
Peter E. Freeman, pfreeman@cmu.edu
Examples
cdfinv("tmean","mean",14.35,s2=4.5,n=22) ## returns 13.40946 15.29054