This is a mistake computing people of my (our?) age often made (make):
determining for the user what is relevant for her. 
The only relevant response I can think of is: Why do you want these
percentiles? 
Perhaps it appears she is helped better with mean value and standard
deviation instead, perhaps not.
If someone in the forum poses a problem, I'm not interested in relevance at
all.

If correctness does not come first, I'm wondering what one is doing. 


R.E. Boss


> -----Oorspronkelijk bericht-----
> Van: [email protected] [mailto:programming-
> [email protected]] Namens Bo Jacoby
> Verzonden: vrijdag 24 september 2010 8:38
> Aan: Programming forum
> Onderwerp: Re: [Jprogramming] Classification problem
> 
> First comes relevance, then correctness, performance, and elegance in some
> order. Not every problem is put right. For example. Question: from a long
> list of numbers, how to compute the 15th, 50th and 85th percentile?
> Answer: Don't do that! Compute the mean value and the standard deviation
> instead.
> Venlig hilsen, Bo
> 
> 
> --- Den tors 23/9/10 skrev Roger Hui <[email protected]>:
> 
> Fra: Roger Hui <[email protected]>
> Emne: Re: [Jprogramming] Classification problem
> Til: "Programming forum" <[email protected]>
> Dato: torsdag 23. september 2010 16.48
> 
> At first I was going to respond to R.E. Boss with a
> cute and annoying reply, something like "first comes
> elegance, then elegance, then elegance".  But I think
> now I agree with him, "first comes correctness, then
> performance, then elegance",  rather than "first comes
> elegance and correctness".  A counterexample to the
> latter is a model for dyadic index-of for vectors.
> An elegant and correct model is:
> 
> ix=: #...@[ - (+/)@(+./\)@(=/)
> 
> But due to abysmal performance this is pretty useless
> in practice.
> 
> I guess it depends on what you mean by "first comes".
> If you were implementing dyadic index-of you _would_
> first writing something like the above, but almost
> immediately you write something else.
> 
> 
> 
> ----- Original Message -----
> From: Robert Raschke <[email protected]>
> Date: Thursday, September 23, 2010 6:57
> Subject: Re: [Jprogramming] Classification problem
> To: Programming forum <[email protected]>
> 
> > I disagree, first comes elegance and correctness, and these tend
> > to go hand
> > in hand if you are concentrating on elegance. I quite strongly
> > believe a
> > human reader is way more important than any machine.
> >
> > Robby
> >
> > On Thu, Sep 23, 2010 at 2:24 PM, R.E. Boss
> > <[email protected]> wrote:
> >
> > > I agree. First comes correctness, then performance, then elegance.
> > >
> > >
> > > R.E. Boss


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