Method and apparatus for generating and/or updating cooccurrence relation dictionary

A method of generating and updating a cooccurrence relation directory in a natural language processing system including an input/output device, a memory for storing therein dictionary information, and a processor for processing an input sentence by use of the dictionary information, the method comprising the steps of:

• effecting a syntactic analysis on the input sentence;
• inspecting ambiguity in predicate-argument relationships included in said input sentence;
• transforming unambiguous predicate-argument relationships obtained as a result of said inspecting into information having a predetermined format;
• registering said transformed unambiguous predicate-argument relationships to said cooccurrence relation dictionary;
• and
• updating a case frame dictionary based on a set of generalizable predicate-argument relationships contained in the cooccurrence relation dictionary stored in said memory, said case frame dictionary including information of case relations satisfiable between a predicate word and an argument thereof.

A natural language processing system including an input/output device, file means for storing therein dictionary information, and processing means for processing an input sentence supplied from the input/output device, using the dictionary information,

• said processing means comprising:
• syntactic analysis means coupled to said input/output device for effecting a syntactic analysis on an input sentence to produce possible predicate-argument relationships;
• ambiguity determining means responsive to said syntactic analysis means for examining ambiguity in said predicate-argument relationships;
• a cooccurrence relation update means for registering in a cooccurrence relation dictionary storing cooccurrence relation information, predicate-argument relationships determined to be unambiguous by said ambiguity determining means, when said predicate-argument relationships are not included in said cooccurrence dictionary;
• and
• case frame file means for constituting therein a case frame dictionary comprising information of a case relation satisfiable between a predicate word and a noun to be governed by the word;
• said processing means referencing said cooccurrence relation dictionary file means and the case frame dictionary file means so as to automatically generalize knowledge accumulated in said cooccurrence relation dictionary file into case frame information, thereby updating said case frame dictionary.

A method of generating and updating a cooccurrence relation directory in a natural language processing system including an input/output device, a memory for storing therein dictionary information, and a processor for processing an input sentence by use of the dictionary information, the method comprising the steps of:

• effecting a syntactic analysis on the input sentence;
• inspecting syntactic ambiguity of said input sentence;
• transforming syntactically unambiguous predicate-argument relationships obtained as a result of said inspecting into information having a predetermined format;
• and
• registering said transformed unambiguous predicate-argument relationships to said cooccurrence relation dictionary.

A method of automatically generating cooccurrence relation information indicating whether a pair of words in a natural language can cooccur using, a memory, sentences, and a processor,

• said method comprising the steps of:
• providing as an input, sentences belonging to a user selected field;
• effecting a syntactic analysis of an input sentence having a set of possible predicate-argument relationships, on the basis of grammatical rules to determine an intermediate representation of the input sentence;
• examining ambiguity in the predicate-argument relationships on the basis of predetermined rules to determine whether each predicate-argument relationship is ambiguous or not;
• and
• selecting predicate-argument relationships which are determined to be syntactically unambiguous from the examination result by said examining, and providing the same as cooccurrence relation information to be registered in a cooccurrence relation dictionary storing cooccurrence relation information.

A natural language processing system including an input/output device, file means for storing therein dictionary information, and processing means for processing an input sentence supplied from the input/output device, using the dictionary information.

• said processing means comprising:
• syntactic analysis means coupled to said input/output device for effecting syntactic analysis on an input sentence to produce possible syntactic structures, each of which is expressed as a set of predicate-argument relationships;
• ambiguity determining means responsive to said syntactic analysis means for examining syntactic ambiguity in said predicate-argument relationships;
• and
• a cooccurrence relation update means for registering in a cooccurrence relation dictionary storing cooccurrence relation information, predicate-argument relationships determined to be syntactically unambiguous by said ambiguity determining means, when said predicate-argument relationships are not included in said cooccurrence dictionary.

A method of supplying information to a cooccurrence relation dictionary of a natural language processing system, wherein the system includes an input/output device which inputs words forming a sentence, a memory for storing information supplied to the cooccurrence relation dictionary, and a processor for processing the input words, the method comprising the steps of:

• inspecting the words input by the input device which are arranged as pairs of words in a predicate-argument relationship to determine whether the pairs of words are syntactically unambiguous;
• registering automatically the pairs of words determined to be syntactically unambiguous to the cooccurrence relation dictionary;
• and
• effecting a syntactic analysis on the input sentence.