On Mon, Aug 4, 2008 at 6:10 PM, YKY (Yan King Yin) <
[EMAIL PROTECTED]> wrote:

> On 8/5/08, Ben Goertzel <[EMAIL PROTECTED]> wrote:
> >
> > As noted there, my impression is that PILP could be implemented within
> OpenCog's PLN backward chainer (currently being ported to OpenCog by Joel
> Pitt, from the Novamente internal codebase) via writing a special scoring
> function ...
>
>
> Yes, I think the inductive search is somewhat similar to backward chaining,
> except that the steps in the inductive search can *create* rules, whereas in
> backward chaining you're applying *existing* rules.
>


Yes, but in PLN/ OpenCogPrime backward chaining *can* create hypothetical
logical relationships and then seek to estimate their truth values

See this page

http://opencog.org/wiki/OpenCogPrime:IntegrativeInference

and the five pages linked to from it (at the top)


>
> We need a scoring function, but I have not thought about this yet.
>
> I think the hardest part is actually in generating the search tree.  You
> see, in first-order logic, rules can involve many predicates, predicates may
> have variables as arguments, and the arguments may even have complex terms
> involving functions.  So the combinatorial explosion is severe.
>

The purpose of the scoring function is precisely to attempt to manage this
combinatorial explosion.


>
> The scoring function may provide a "gradient" over the search space, so you
> suggested to use hill-climbing.  But I suspect that such a gradient is not
> useful during the search, because the search space is discrete and
> irregular, and the scores probably jump irregularly from node to node.
> That's why I suspect that hill-climbing is not useful here.
>

As noted in one of the pages mentioned above,

http://opencog.org/wiki/OpenCogPrime:HebbianInferenceControl

I believe that the only solution to this problem is not algorithmic, but
architectural: we need to mine the data-store of historical inferences

http://opencog.org/wiki/OpenCogPrime:InferencePatternMining

and  use this information to provide inductive bias to be used within the
scoring function itself.

-- Ben G



-------------------------------------------
agi
Archives: https://www.listbox.com/member/archive/303/=now
RSS Feed: https://www.listbox.com/member/archive/rss/303/
Modify Your Subscription: 
https://www.listbox.com/member/?member_id=8660244&id_secret=108809214-a0d121
Powered by Listbox: http://www.listbox.com

Reply via email to