From feh3k at spamcop.net  Mon Jan 19 19:26:54 2004
From: feh3k at spamcop.net (Frank E Harrell Jr)
Date: Mon Jan 19 19:25:52 2004
Subject: [Rd] Wish list
In-Reply-To: <Pine.LNX.4.44.0401191810230.5031-100000@gannet.stats>
References: <20040119130316.5462409c.feh3k@spamcop.net>
	<Pine.LNX.4.44.0401191810230.5031-100000@gannet.stats>
Message-ID: <20040119132654.3812139d.feh3k@spamcop.net>

On Mon, 19 Jan 2004 18:13:42 +0000 (GMT)
Prof Brian Ripley <ripley@stats.ox.ac.uk> wrote:

> On Mon, 19 Jan 2004, Frank E Harrell Jr wrote:
> 
> > On Mon, 19 Jan 2004 17:17:39 +0000 (GMT)
> > Prof Brian Ripley <ripley@stats.ox.ac.uk> wrote:
> > 
> > > Are you sure there is a measurable difference in calling methods
> > > directly? The dispatch overhead on formula (one of your uses)
> > > appears to be about 10 microseconds.  (Note, negligible even for
> > > 10,000 bootstraps.)
> > > 
> > > I believe we took the real performance penalties into account (and 
> > > namespaces had performance pluses as well as minuses).
> > 
> > Brian,
> > 
> > I don't worry about dispatch overhead.  I do worry about overhead of
> > assembling model matrices, removing rows with NAs, etc.  -Frank
> 
> Here is what you said:
> 
> > The point of calling methods directly is efficiency, otherwise I would
> > not use this dirty practice.  When bootstrapping or otherwise calling
> > methods
> 
> and your code is failing in R-devel because you are calling
> formula.default. So, *why* are you calling formula.default?

That was fixed 16Dec03 for the next version to be submitted to CRAN.  I no
longer call formula.default.

> 
> Calling e.g. glm.fit not glm is not to do with methods, and apparently
> survfit.km is not a method.

You're right, it just has to do with survfit.km needing to be exported.

Frank
---
Frank E Harrell Jr   Professor and Chair           School of Medicine
                     Department of Biostatistics   Vanderbilt University


[Rd] Wish list
Frank E Harrell Jr