Re: R-beta: quantile

Peter Dalgaard BSA (p.dalgaard@biostat.ku.dk)
27 Feb 1998 00:08:19 +0100


To: Bill Simpson <wsimpson@uwinnipeg.ca>
Subject: Re: R-beta: quantile
From: Peter Dalgaard BSA <p.dalgaard@biostat.ku.dk>
Date: 27 Feb 1998 00:08:19 +0100
In-Reply-To: Bill Simpson's message of Thu, 26 Feb 1998 16:36:03 -0600 (CST)

Bill Simpson <wsimpson@uwinnipeg.ca> writes:

> 
> I do:
> x<-rnorm(1000)
> quantile(x,c(.025,.975))
>        2%       98% 
> -1.844753  1.931762 
> 
> Since I want to find a 95% confidence interval, I take the .025 and .975
> quantiles.  HOWEVER R says I have the 2% (not 2.5%) and 98% (not 97.5%)
> points.  Is it just rounding the printed 2% and 98%, or is it REALLY
> finding .02 and .98 points instead of .025 and .975?

It's rounding... 

At the end of the quantile function, you'll see:

        names(qs) <- paste(round(100 * probs), "%", sep = "")
        qs
}

Maybe we should put in an extra argument for controlling the precision
of the rounding?

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard@biostat.ku.dk)             FAX: (+45) 35327907

-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._