From ben.bob at gmail.com  Tue Aug 30 00:03:06 2005
From: ben.bob at gmail.com (Bo Peng)
Date: Mon, 29 Aug 2005 15:03:06 -0700
Subject: [Rd] efficiency of sample() with prob.
In-Reply-To: <Pine.LNX.4.61.0508291607080.6766@gannet.stats>
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	<6ea7b54305062211146473e7bf@mail.gmail.com>
	<Pine.LNX.4.61.0506222005080.3592@gannet.stats>
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	<Pine.LNX.4.61.0508291607080.6766@gannet.stats>
Message-ID: <6ea7b54305082915037905dc2f@mail.gmail.com>

> It seems the distribution used for your tests is maximally favourable to 
> your proposal (not uncommon in papers, but not very honest).  

I did not have time to do a thorough test. I was simply reporting what
I had done so any implied dishonesty is unfair to me.

> Changing how this is done will break the reproducibility of past programs,
> and we don't really want to introduce yet more options.  So it seems only
> worth doing when there are substantial speed gains. 

I agree that Walker's method may be slow at some cases but there is
nothing to brag about R's current method either. The bottom line is: a
bisection method will be uniformly better than the linear search
method that R uses right now. This does not qualify as 'substantial
speed gain' though.

Cheers,
Bo



[Rd] efficiency of sample() with prob.
Bo Peng