Vulcan/TextualMatching

By Stephen Soderland.

Overview

Rules should be human readable and based on textual tuples. They should be in a format that is easy for manual creation and editing. The human-readable rules can be automatically transformed into TUFFY format.

The set of facts used by the system are stored as textual tuples with a link to the sentence and the genre (e.g. definition, study guide, ClueWeb). These tuples may be nested or n-ary, and may have null arg2 for intransitive relations. These tuples can be automatically transformed into TUFFY format.

Rule: <id> (Arg|Rel) : (<var>|<string>) => (Arg|Rel) : (<var>|<string>) <comment>

Notes: Rule looks for exact string match in either an Arg or Rel phrase can be X, Y, Z, R,… and must match any other instances of same variable. <comment> may be displayed in derivation

Example 1

Question to demonstrate: “Growth causes leaves of a plant to become large”.

(growth, cause,  (leaves of a plant, become large))	[nested, with intransitive arg2] 
(growth, cause,  (leaves of a plant, become, large))	[nested, with binary rel for arg2]

Evidence from definition: “The noun growth is the process of something becoming bigger”

(growth, is process of, (something, become bigger)
(growth, is process of, (something, become, bigger))

Rules needed

1. Rel: X  =>  Rel: is process of	        [generalize any action to “is process of”]
1a. Rel: cause  =>  Rel: is process of 	        [more particular version of rule 2] 
2. Rel: is process of  =>  Rel: X 	        [abductive rule, inverse of rule 1] 
2a. Rel: is process of  =>  Rel: cause	        [abductive rule, inverse of rule 1a]
3. Arg: X  => Arg: something	                [generalize any arg value to “something”]
4. Arg: something  =>  Arg: X	                [abductive rule, inverse of rule 3]
5. Rel: become bigger   =>  Rel: become big	[lexical substitution from verb stemmer]
6. Rel: become big  =>  Rel: become large	[lexical substitution from WN synonym]

Notes on rules:

We can derive abductive inverses automatically with a meta-rule. Lexical substitution rules are generated on the fly as needed.

Derivation

Evidence: 
	(growth, is process of, (something, become bigger)) 
Rel: become bigger   =>  Rel: become big
	(growth, is process of, (something, become big))
Rel: become big  =>  Rel: become large
	(growth, is process of, (something, become large))
Arg: something  =>  Arg: X
	(growth, is process of, (leaves of a plant, become large))
Rel: is process of  =>  Rel: X
	(growth, cause,  (leaves of a plant, become large))   QED

  Example 2

Question to demonstrate: “A sense of smell helps a fox find food”

(sense of smell, helps,  (fox, find, food))

Evidence from Study Guide: “A good sense of smell is necessary for many animals to find food.”

(good sense of smell, is necessary for, (animal, find, food))

Rules needed

7. Rel: is necessary for  =>  Rel: helps	        [a textual entailment]
8. Arg: fox  =>  Arg: animal	                        [lexical substitution from WN hypernym]
9. Arg: animal  => Arg: fox	                        [lexical specialization from WN hypernym]
10. Arg: X Y  => Arg: Y	                                [generalize by dropping modifier] 
10a. Arg: good Y  => Arg: Y	                        [more particular version of rule 10] 
10b. Arg: good sense of smell  => Arg: sense of smell	[more particular version of rule 10a] 
11. Arg: Y  => Arg: X Y	                                [abductive inverse of rule 10]
11a. Arg: Y  => Arg: good Y	                        [more particular version of rule 11] 
11b. Arg: sense of smell => Arg: good sense of smell	[more particular version of rule 11a]

Note on rules: 10 and 10a are in the nature of meta-rules – TUFFY gets the particular rule 10b. Same with 11, 11a, 11b.

Derivation

Evidence: 
	(good sense of smell, is necessary for, (animal, find, food)) 
Arg: good Y  => Arg: Y
	(sense of smell, is necessary for, (animal, find, food)) 
Arg: animal  => Arg: fox
	(sense of smell, is necessary for, (fox, find, food)) 
Rel: is necessary for  =>  Rel: helps
	(sense of smell, helps, (fox, find, food))