Systems and methods for detecting entailment and contradiction

• US 7,313,515 B2
• Filed: 05/01/2006
• Issued: 12/25/2007
• Est. Priority Date: 05/01/2006
• Status: Expired due to Fees

• Current Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Original Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Inventors: Crouch, Richard S., Holloway King, Tracy
• Primary Examiner(s): Hudspeth, David
• Assistant Examiner(s): ALBERTALLI, BRIAN LOUIS
• Application Number:
  US11/415,609
• Publication Number:
  US 20070255555A1
• Time in Patent Office: 603 Days
• Field of Search: None
• US Class Current: 704/9
• CPC Class Codes: G06N 5/02 Knowledge representation; Symbolic representation

Abstract

Techniques are provided for detecting entailment and contradiction. Packed knowledge representations for a premise and conclusion text are determined comprising facts about the relationships between concept and/or context denoting terms. Concept and context alignments are performed based on alignments scores. A union is determined. Terms are marked as to their origin and conclusion text terms replaced with by corresponding terms from the premise text. Subsumption and specificity, instantiability, spatio-temporal and relationship based packed rewrite rules are applied in conjunction with the context denoting facts to remove entailed terms and to mark contradictory facts within the union. Entailment is indicated by a lack of any facts from the packed knowledge representation of the conclusion in the union. Entailment and contradiction markers are then displayed.

Claims

1. A system for indicating entailment and contradiction in text comprising:

a packed knowledge representation manager that determines premise and conclusion packed knowledge representations, the premise and conclusion packed knowledge representations each including premise and conclusion facts about relationships between concept terms;

a concept alignment manager that aligns corresponding concepts between the premise packed knowledge representation and the conclusion packed knowledge representation; and

an entailment/contradiction manager that determines a concept aligned union of the packed knowledge representations of the premise and the conclusion with concept terms marked as to origin and which substitutes relevant packed knowledge representation concept terms for comparison, removes concept terms based on a plurality of entailment/contradiction rules retrieved from an entailment/contradiction rule storage and indicates entailment and contradiction.

2. The system of claim 1, in which a knowledge representation is comprised of hierarchical concept information elements from an ontology and relationship elements specifying relationships between the concept elements and concept element instances.

3. The system of claim 1, further comprising a context alignment circuit that aligns contexts between the premise packed knowledge representation and the conclusion packed knowledge representation, the premise and conclusion packed knowledge representations each further including premise and conclusion facts about relationships between context terms.

4. The system of claim 1, further comprising a display manager that displays the indicated entailment and contradiction on a display device.

5. The system of claim 1, in which the premise and conclusion terms are combined in a union.

6. The system of claim 1, in which at least one of:

entailed and contradicted terms, are marked.

7. The system of claim 1, in which at least one of:

entailed and contradicted terms, are indicated.

8. The system of claim 7, in which the entailment is indicated by at least one human sensible display characteristic.

9. A method for indicating entailment and contradiction comprising the steps of:

determining premise and conclusion packed knowledge representations, the premise and conclusion packed knowledge representations each including premise and conclusion facts about relationships between concepts;

determining concept alignments for concepts within the premise and conclusion packed knowledge representations;

detecting entailment and contradiction in the packed knowledge representations based on the concept alignments and a set of entailment and contradiction detection rewrite rules.

10. The method of claim 9, in which the packed knowledge representations are based on natural language text.

11. The method of claim 10, in which the source of the natural language text is at least one of:

a written text and non-written text.

12. The method of claim 11, in which the non-written natural language source is at least one of:

audio and visual information.

13. The method of claim 12, in which the visual information is at least one of:

sign language and a communicative gesture.

14. The method of claim 12, in which the audio and visual information is automatically recognized to a text.

15. The method of claim 9, in which the packed knowledge representation is based on packed structures determined from the premise and the conclusion texts.

16. The method of claim 15, packed representations are at least one of:

packed f-structures, packed semantic representations, packed knowledge representations.

17. The method of claim 15, in which the entailment and contradiction detection rules are based on at least one of:

subsumption, specificity, instantiability, roles, cardinality and relationship information.

18. The method of claim 17, in which the relationships information includes at least one of:

spatial and temporal relationship information.

19. The method of claim 17, in which the specificity information is determined using an ontological hierarchy.

20. The method of claim 19, in which the specificity information is based on role restrictions.

21. The method of claim 9, in which the packed knowledge representations are associated with at least one of:

unambiguous text and disambiguated packed representations.

22. A computer readable storage medium comprising computer readable program code embodied on the computer readable storage medium, the computer readable program code useable to program a computer to indicate textual entailments and contradictions comprising the steps of:

determining premise and conclusion packed knowledge representations, the premise and conclusion packed knowledge representations each including premise and conclusion facts about relationships between concepts;

determining concept alignments for concepts within the premise and conclusion packed knowledge representations;

detecting entailment and contradiction in the packed knowledge representations based on the concept alignments, the context alignments and a set of entailment and contradiction detection rewrite rules.

23. A computer implemented method for conceptually aligning premise and conclusion texts comprising the steps of:

determining packed knowledge representations for the premise and conclusion texts, the packed knowledge representations each including premise and conclusion facts about relationships between concepts related to the premise and conclusion texts;

determining concept alignments for concepts within the packed knowledge representations of the premise and the conclusion;

displaying the aligned packed knowledge representations.