Re: A new proof of the superiority of set oriented approaches: numerical/time serie linear interpolation
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Thu, 03 May 2007 12:16:54 -0300
Message-ID: <4639fcb7$0$4042$9a566e8b_at_news.aliant.net>
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> Brian
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>
> He
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> of
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> I apologize for my part in hijacking your thread.
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> One thing you might want to pursue that would interest me is "what kinds of
> data lend themselves to interpolation, regression, or any other kind of
> smoothing, and what kinds do not."
>
> If we know that on June 10, a certain person's name was Mary Smith, and on
> September 3, her name was Mary Jones, interpolation is not going to help
> us figure out her name on sugust 17.
>
> Is it only numerical data that lend themselves to the kind of approximation
> and/or inference that you are exploring?
Date: Thu, 03 May 2007 12:16:54 -0300
Message-ID: <4639fcb7$0$4042$9a566e8b_at_news.aliant.net>
David Cressey wrote:
> "Cimode" <cimode_at_hotmail.com> wrote in message
> news:1178192551.663643.78380_at_o5g2000hsb.googlegroups.com...
>
>>On May 3, 12:05 pm, "David Cressey" <cresse..._at_verizon.net> wrote: >> >>>"Cimode" <cim..._at_hotmail.com> wrote in message >>> >>>news:1178174344.866049.272810_at_h2g2000hsg.googlegroups.com... >>> >>> >>> >>> >>>>On 2 mai, 21:47, paul c <toledobythe..._at_oohay.ac> wrote: >>>> >>>>>Cimode wrote: >>> >>>>>... >>> >>>>>>Brian, >>> >>>>>>Don't you think you are overcomplicating things? >>> >>>>>I certainly do. RT isn't as complicated or subtle as this thread is >>>>>making it out to be. >>>> >>>>I was not thinking about *subtleness*. I am having trouble following >>>>Brian's wordy line of thought. I am not sure he and I have do not >>>>have the same perception of what logical and physical independence >>>>is. I was also refering to terms I am not familiar with such as >>>>*database state*. To me they are totally foreign to RM formal >>>>theory. >>> >>>>Maybe you could clarify. Thanks. >>>>Regards... >>> >>>>[Snipped] >>> >>>I think that "state" is a fundamental concept in computing. As such,
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> Brian
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>>>and others ought to be able to use it to communicate rather precisely, >>>without needing to present a formal definition. If you know what a >>>"database" is and you know what a "state" is, I think you know what a >>>"database state" is. >>> >>>Having said that, I'll admit that I'm often lost by Brian's argument.
>
> He
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>>>seems to be arguing that transaction atomicity is an undesirable feature
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> of
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>>>our data model. If I'm reading that right, I abandon the effort to >>>understand the rest of what he's saying. >> >>I am not sure formal theory requires the need for *state* concept. >>The fundamental concepts of relation value, relations variable or >>simply relation are sufficient to describe the evolution of a specific >>relation in time. What does bringing concepts that are clearly OO >>oriented (I have heard about db *state*, db *instantiation*, db >>*instance*) add to the equation? Not much I am afraid.
Cimode has things backward. Instantiation is a logical concept and the OO folks borrowed the word from logic. One creates a proposition by instantiating a predicate.
I see no reason to abandon the word just because someone borrowed it for something else.
>>Quite frankly, I am not interested that much into a terminology debate >>but rather into *how interpolation could eventually serve as a way to >>handle missing information*. So far, Vadim has brought some >>interesting insight through the addition of a theorical regression >>method implemented in SQL (I will try to adapt it as soon as I find >>sometime). I am afraid the discussions about *design quality*, *SQL >>critiscism* are in fact off topic.
>
> I apologize for my part in hijacking your thread.
>
> One thing you might want to pursue that would interest me is "what kinds of
> data lend themselves to interpolation, regression, or any other kind of
> smoothing, and what kinds do not."
>
> If we know that on June 10, a certain person's name was Mary Smith, and on
> September 3, her name was Mary Jones, interpolation is not going to help
> us figure out her name on sugust 17.
>
> Is it only numerical data that lend themselves to the kind of approximation
> and/or inference that you are exploring?
Interpolation has a number of other traps. Suppose one evaluates: f(x) = (x-1)/(x-1) at x=0 and x=2. One will reach a vastly wrong conclusion if one even tries to interpolate f(1). Received on Thu May 03 2007 - 17:16:54 CEST