Message-ID: <Pine.LNX.4.44.0304012023250.12034-100000@gannet.stats>
Date: 2003-04-01T19:45:16Z
From: Brian Ripley
Subject: cor.test observations limit
In-Reply-To: <3.0.5.32.20030401135701.009f71a0@host2a.emmes.com>
Yes. About 1290 for the Spearman test.
You need (n^3 - n) representable as an integer.
On Tue, 1 Apr 2003, Ming-Chung Li wrote:
> Is there a limit on the number of observations for using cor.test. For
> example,
>
> > library(ctest)
That's not needed, and has not been for about 3 years.
> > cor.test(rnorm(3000), rnorm(3000), method="spearman")
> Error in if (q > (n^3 - n)/6) pspearman(q - 1, n, lower.tail = FALSE) else
> pspearman(q, :
> missing value where logical needed
> In addition: Warning message:
> NAs introduced by coercion
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595