From wsimpson@uwinnipeg.ca  Thu Sep  3 16:57:41 1998
From: wsimpson@uwinnipeg.ca (Bill Simpson)
Date: Thu, 3 Sep 1998 10:57:41 -0500 (CDT)
Subject: ppoints
Message-ID: <Pine.OSF.3.95.980903105649.11084A-100000@io.uwinnipeg.ca>

When I look at ppoints I see:

ppoints<-function (x) 
{
n <- length(x)
if (n == 1) 
	n <- x
(1:n - 0.5)/n
}

However Venables & Ripley (2nd ed, p 165) say ppoints() should return
(i-1/2)/n for n>=11; (i-3/8)/(n+1/4) for n<=10.

The version below should work as described:

ppoints<-function (x) 
{
n <- length(x)
if (n <= 10)
	(1:n - 0.375)/(n + 0.25) 
else
	(1:n - 0.5)/n
}

Bill Simpson

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ppoints
Bill Simpson