From Jerry.Lewis at biogenidec.com  Tue Nov 17 05:05:10 2009
From: Jerry.Lewis at biogenidec.com (Jerry.Lewis at biogenidec.com)
Date: Tue, 17 Nov 2009 05:05:10 +0100 (CET)
Subject: [Rd] pt not monotonic with large noncentrality (PR#14069)
Message-ID: <20091117040510.193382830317@mail.pubhealth.ku.dk>

Full_Name: Jerry W. Lewis
Version: 2.10.0
OS: Windows XP Professional
Submission from: (NULL) (96.237.55.233)


pt(0,3,200)      # correctly returns 0
pt(-1000,3,200)  # erroniously returns 0.003116595

Since pt(0,df,nc) = pnorm(-nc), there is an easily computed upper bound for
pt(-t,df,nc) where t>0 and nc>0.



[Rd] pt not monotonic with large noncentrality (PR#14069)
Jerry.Lewis at biogenidec.com