Joint disambiguation of syntactic and semantic ambiguity

• US 20110125487A1
• Filed: 11/20/2009
• Published: 05/26/2011
• Est. Priority Date: 11/20/2009
• Status: Active Grant

• Current Assignee: Postq IPR OY
• Original Assignee: TATU Ylonen OY Limited
• Inventors: Ylonen, Tatu J.
• Granted Patent: US 8,504,355 B2
• Time in Patent Office: Days
• US Class Current: 704/9
• CPC Class Codes: G06F 40/211 Syntactic parsing, e.g. based on context-free grammar [CFG] or unification grammars
• CPC Class Codes: G06F 40/30 Semantic analysis

Abstract

Ambiguities in a natural language expression are interpreted by jointly disambiguating multiple alternative syntactic and semantic interpretations. More than one syntactic alternative, represented by parse contexts, are analyzed together with joint analysis of referents, word senses, relation types, and layout of a semantic representation for each syntactic alternative. Best combinations of interpretations are selected from all participating parse contexts, and are used to form parse contexts for the next step in parsing.

Claims

1. A method of resolving both semantic and syntactic ambiguity, comprising:

generating, by a computer, combinations of semantic interpretation choices for each of at least two alternative syntactic parses of a natural language expression or part thereof; and

selecting, by the computer, one or more best combinations from those generated for all of the alternative syntactic parses.

2. The method of claim 1, wherein the computer comprises a multi-context disambiguator.

3. The method of claim 2, further comprising:

enumerating more than one choice for at least one semantically ambiguous aspect of at least one of the alternative syntactic parses.

4. The method of claim 2, wherein at least one constituent that occurs in more than one alternative syntactic parse is enumerated only once, and the resulting choices are combined into combinations for more than one of the alternative syntactic parses.

5. The method of claim 1, wherein the alternative syntactic parses participating in the disambiguation are selected by grouping alternative syntactic parses based on their current state and states in their stack.

6. The method of claim 1, wherein the disambiguation is performed in connection with combining stacks.

7. The method of claim 1, wherein the disambiguation is performed in connection with local ambiguity packing.

8. The method of claim 1, wherein the disambiguation is performed in connection with combining nodes in a chart parser.

9. The method of claim 1, wherein each combination comprises exactly one choice for each ambiguous aspect in the corresponding alternative syntactic parse.

10. The method of claim 1, wherein combinations generated for two alternative syntactic parses comprise a different number of choices.

11. The method of claim 1, wherein combinations are collected from several combinators (119) for selection by a single selector (308).

12. An apparatus comprising:

a multi-context disambiguator (115), comprising;

at least one enumerator;

at least one combinator (119) coupled to at least one of the enumerators for receiving choices from the enumerator; and

at least one selector (308) coupled to the combinators for selecting at least one best combination from the combinations generated by any of the combinators.

13. The apparatus of claim 12, wherein at least one enumerator is coupled to more than one combinator.

14. The apparatus of claim 12, wherein the multi-context disambiguator comprises only one combinator.

15. The apparatus of claim 12, wherein the apparatus is a computer.

16. The apparatus of claim 12, wherein the apparatus is a robot.

17. The apparatus of claim 12, wherein the apparatus is a home or office appliance.

18. A computer readable medium comprising a computer program product, which when executed on a computer is operable to cause the computer to resolve both semantic and syntactic ambiguity in a parsed natural language expression, the medium comprising:

a computer readable program code means for causing a computer to generate combinations of semantic interpretation choices for each of at least two alternative syntactic parses of a natural language expression or part thereof; and

a computer readable program code means for causing a computer to select one or more best combinations from those generated for all of the alternative syntactic parses.