[Top] [All Lists]

Re: [ontolog-forum] Webby objects

To: Amanda Vizedom <amanda.vizedom@xxxxxxxxx>
Cc: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Edward Barkmeyer <edward.barkmeyer@xxxxxxxx>
Date: Mon, 19 Nov 2012 16:44:25 -0500
Message-id: <50AAA839.5000107@xxxxxxxx>
I think Amanda is right about getting lost in the academic descriptions 
of the properties of reasoners and languages.  I phrased my concerns 
inappropriately, it seems.    (01)

John Sowa originally wrote that no user asks for decidability, users 
always ask for more expressiveness.  I have yet to hear a user ask for 
either.  Industry users are interested in capability and performance.  
They ask for more capability, but they want a guarantee of performance.  
"Capability" is the combination of an expressive language for axioms and 
questions and the availability of a reasoning tool that uses them to 
return answers.  Performance is the returning of answers in a reasonable 
length of time.    (02)

Amanda Vizedom wrote:    (03)

> The real valuable work comes from identifying logic languages and 
> procedures, that maximize expressiveness, usability, and reasoning 
> within the domain of statements and tasks the user needs. That is more 
> complex and subtle.    (04)

Exactly.     (05)

> There are lots of ways to design systems to either disallow certain 
> statements (IMHO, better done semantically than 
> via unusably counter-intuitive or restricted syntax), or decline to 
> process certain reasoning patters that have a high rabbit-hole risk, 
> or cut out after a certain time, or use other techniques to tune 
> performance. The line between decidable and undecidable systems is not 
> a sweet spot for this.    (06)

Of course.  But the line between DLs and FOLs *is* a sweet spot for 
this.  There are many industry applications that can be met by DLs with 
their measurable performance, in spite of the fact that their 
expressiveness is limited and some of the axiom formulations are hard 
for human experts to read.  The land of FOLs is significantly more 
expressive, but it has many more cliffs and sinkholes that make it much 
more difficult to predict performance.    (07)

> For all of these reasons, IMHO, decidability is a red herring. Worse, 
> and to mix my metaphors, it is a red herring that has led far too many 
> talented people on a wild goose chase when they could be doing much 
> more useful work to advance the state of the science and technology in 
> really valuable ways.    (08)

I'm not so sure that academic pursuits like decidability actually lead 
talented people away from useful work.  We have a rule that a Ph.D. has 
to advance the state of the art.  It means that to get a Ph.D from a 
prestigious institution will require you to do a few years work in some 
esoteric field like decidability.  In the course of that work, you will 
learn what all the academic terminology means, how the concept space is 
related, and what the state of the art actually is.  When you have the 
degree, you can start doing "useful" things, that use some parts of the 
knowledge you gained, and the skills you gained in comprehending 
ill-written technical literature.  It is unlikely that you will have a 
direct application for what you know about decidability, but it is 
equally unlikely that a talented mathematician will find an industry 
application for counting graphs or proving the convergence of Sobolev 
methods, or that a botanist will find industry application for isolating 
cabbage genomes.  The loss only occurs when the talented student isn't 
prepared for the fact that industry is more interested in what else s/he 
knows, and continues looking for interest in his/her academic 
specialty.  The purely academic pursuit is part of the rite of passage, 
and the maintenance of expertise in it may later be important in guiding 
others.  The truly talented people will find useful things to do; the 
others are just intellectually gifted.  It takes most of us a long time 
to understand what knowledge we really have and what its value is.  Some 
of the gifted never do.    (09)

-Ed    (010)

> Best,
> Amanda 
> On Mon, Nov 19, 2012 at 1:52 PM, Ed Barkmeyer <edbark@xxxxxxxx 
> <mailto:edbark@xxxxxxxx>> wrote:
>     [snip]
>     Everyone agrees that FOL is more expressive and potentially more
>     useful,
>     but all of the reasoning procedures that are widely used in academia
>     either restrict the allowable FOL inputs in some way that greatly
>     reduces its expressiveness or are programmed to throw up their
>     hands at
>     some point -- they "halt" by saying "not determinable" (in some
>     language).  The problem of not knowing the relationship between input
>     data -- the sets of valid sentences -- and the "not determinable"
>     result
>     is what causes industry to shy away from FOL reasoners.
>     [sniip]
>    (011)

Edward J. Barkmeyer                        Email: edbark@xxxxxxxx
National Institute of Standards & Technology
Systems Integration Division, Engineering Laboratory
100 Bureau Drive, Stop 8263                Tel: +1 301-975-3528
Gaithersburg, MD 20899-8263                Cel: +1 240-672-5800    (012)

"The opinions expressed above do not reflect consensus of NIST, 
 and have not been reviewed by any Government authority."    (013)

Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J    (014)

<Prev in Thread] Current Thread [Next in Thread>