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Re: Nested Sets vs. Nested Intervals

From: Mikito Harakiri <mikharakiri_nospaum_at_yahoo.com>
Date: 12 Nov 2005 13:40:00 -0800
Message-ID: <1131831600.872639.118930@z14g2000cwz.googlegroups.com>


amado.alves_at_netcabo.pt wrote:
> Yes, it is essential to provide more compact representations, for
> semantic structures, than the Mneson Calculus or the base graph, for
> cases where the MC or the base graph inflates the number of calculus or
> graph elements. One such case is the attribute structure, so I'll
> discuss this case briefly. Note it equates a labeled edge.
>
> attr. name
> subject -------------> value
>
> Replacing the attribute topologies in the base graph for labelled edges
> should reduce the edge count by 2 or 3 times. Try it.

A labeled edge

         attr. name
subject -------------> value

give rise to ambiguity

                   subject

attr.name -------------> value

(and all the other possible permutations of the 3 elements).

Well, actually I found some examples on your slides http://www.liacc.up.pt/~maa/mneson/unh.pdf These graphs seems to be subgraphs of lattice structures from formal concept analysis.
http://www.upriss.org.uk/papers/arist.pdf Note that objects are positions in the bottom of the graph on figure 2 as the lattice atomic elements. The attributes are on the top. You have attributes on the left, and objects on the right.

Nobody said the other models don't have the right to exist. Hey, there is even connection of formal concept analysis to relational algebra. It is simply that the alternative models are less mature and never enjoyed the same level of success as RM. Received on Sat Nov 12 2005 - 15:40:00 CST

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