Path: news.mathworks.com!not-for-mail
From: "Tom Lane" <tlane@mathworks.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: coxphfit in Statistics toolbox
Date: Tue, 29 Apr 2008 10:33:36 -0400
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> The "censoring" option for coxphfit in the Statistics
> toolbox has the following definition in the Matlab documents
> "A boolean array of the same size as Y that is 1 for
> observations that are right-censored and 0 for observations
> that are observed exactly." This is exactly opposite to the
> common definition in the literature in which 1 is for
> observations that are observed exactly (true event) and 0 is
> for right-censored observations. Is it a typo in the
> documents or the definition of censoring in the Matlab code
> is really like that (i.e., opposite to the commonly used one)?

Jerry, it really is like that.  In MATLAB, 1 is "true," and since the 
argument is called "censoring" it indicates observations that are censored.

I've seen both usages in different references.  If you think there's an 
authoritative reference that's opposite what this function expects, please 
let me know.

-- Tom