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The Concept
• Convert free text into a structure that captures objects, relations, existential, propositional and temporal logic – the whole thing, no excuses.
• Resolve the anaphora.• Build a query in the same structure using free
text• Run the query against the structure using
structure matching and Constraint Reasoning
Close Integration
The search query is built by the same text to structure converter used on the source text
with the same abilities - multiple sentences in a discourse- anaphora resolution so the query can be built
up naturally- switching of interrogative form into
declarative form so there will be a direct match
- use of knowledge already gained as reading proceeds
Search Behaviour – Use What Is There
This relation searches for other ToOwn relations which match it in terms of its parameters – it finds what is already there. ToOwn happens to be transitive, so it expands from its start point – that is, if A owns B and B owns C then A owns C
Searching Behaviour – Go Active
The Detail relation takes its input, and then finds everything connected to the input to create its output – it searches actively around what it is given, rather than being limited to children
Search Behaviour - Chameleon
This relation finds what is there, but must become every other possible relation in the process of finding the information –
• It was omitted• The report doesn’t mention it• We didn’t include it• I wanted to put it in, but Fred said no
Getting From One Relation To Another
SynonymMaps, synonyms and antonyms are used to expand the search to find all relations which may convey the information
Some Numbers
1
32
175
7
7
Pruning flows back and forth – starting at 1, going to 32, to 175, then back to 7Some relations generate large numbers of possibilities, other relations prune them
Consistent Reasoning
There were thirty two subsidiaries found initially, but omission of information found on only a few of those – the excess subsidiaries are pruned, so that all sets of objects throughout the query structure are consistent
Consistent reasoning allows information to flow in any direction, and propagation continues until everything is consistent
In this case, the consistent reasoning model is being dynamically created from the text of the query as soon as it is entered
Similarities with SQL
• Some similarities with an SQL query – very many differences
• The query can be at multiple levels- “Does John intend to own…”
• The relation can be a variable• Passing from one relation to another – Omit to Exclude
to false Include to false Mention• The query is being expanded within the structure to
catch every possible way the required information could have been said
• The query can go active• Pruning of alternatives can flow back and forth, unlike
SQL
Why Was What
Queries which match structure directly
What – the relation is matched against other relations to find out what “what” is
Was – A logical (or existential) is sought, by matching relations
Why – “why” becomes “what causes”, and matches the relation it controls
Why Do It This Way
• Conversion of the text into a resolved structure speeds up searching
• The points where the query anchors are the points where search should occur – it doesn’t read the text, it searches around the nodes in the network where it already is, or moves along links to anaphora far away in the text
• It can handle an explosion of possibilities at close range