Automatic method of generating thematic summaries

• US 5,689,716 A
• Filed: 04/14/1995
• Issued: 11/18/1997
• Est. Priority Date: 04/14/1995
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Chen, Francine R.
• Primary Examiner(s): Nguyen, Phu K.
• Application Number:
  US08/422,573
• Time in Patent Office: 949 Days
• Field of Search: 364/419.19, 364/419.09, 395/155, 395/161, 395/761
• US Class Current: 715/256
• CPC Class Codes: G06F 16/345 Summarisation for human users
• CPC Class Codes: G06F 40/30 Semantic analysis
• CPC Class Codes: G06F 40/35 Discourse or dialogue representation

Abstract

A technique for automatically generating thematic summaries for machine readable representations of documents. The technique begins with determining the number of thematic terms to be used based upon the number of thematic sentence to be extracted. To insure some commonality of theme between extracted sentences, the number of thematic terms used should be less than the number of thematic sentences to be extracted. Having determined the appropriate number of thematic terms, next the method identifies the thematic terms within the document. Afterward, each sentence of the document is scored based upon the number of thematic terms contained within the sentence. The desired number of highest scoring sentences are selected as thematic sentences.

Claims

1. A processor implemented method of generating a thematic summary of a document presented in machine readable form to the processor, the document including a first multiplicity of sentences and a second multiplicity of terms, the processor implementing the method by executing instructions stored in electronic form in a memory device coupled to the processor, the processor implemented method comprising the steps of:

a) determining a value of a first number of thematic terms based upon a value of a second number representing a length of the thematic summary, the first number being less than the second number;

b) selecting the first number of thematic terms from the second multiplicity of terms;

c) scoring each sentence of the first multiplicity of sentences based upon occurrence of thematic terms in each sentence; and

d) selecting the second number of thematic sentences from the first multiplicity of sentences based upon the score of each sentence.

2. The processor implemented method of claim 1 further comprising the step of:

e) presenting the thematic sentences to user of the processor in an order in which the thematic sentences occur in the document.

3. The processor implemented method of claim 1 wherein step c) comprises incrementing the score of each sentence for each thematic term occurring in the sentence by an amount related to the frequency of occurrence of the thematic term within the document.

4. The processor implemented method of claim 1 prior to step a) further comprising the steps of:

e) receiving the value of the second number from an input device coupled to the processor.

5. The processor implemented method of claim 4 wherein the first number is at least three.

6. A processor implemented method of generating a thematic summary of a document presented in machine readable form to the processor, the document including a first multiplicity of sentences and a second multiplicity of terms, the processor implementing the method by executing instructions stored electronically in a memory device coupled to the processor, the processor implemented method comprising the steps of:

a) determining a value of a first number of thematic terms based upon a value of a second number representing a length of the thematic summary, the first number being less than the second number;

b) determining a number of times each term of the second multiplicity of terms occurs in the document,

c) selecting the first number of thematic terms from the second multiplicity of terms based upon the number of times each term occurs in the document;

d) scoring each sentence of the first multiplicity of sentences based upon occurrences of thematic terms within each sentence; and

e) selecting the second number of thematic sentences from the first multiplicity of sentences based upon the sentence scores.

7. The processor implemented method of claim 6 further comprising the step of:

f) presenting the thematic summary to a user of the processor by presenting the thematic sentences in an order in which they occur in the document.

8. The computer implemented method of claim 7 wherein step d) comprises incrementing the score of each sentence for each thematic term occurring in the sentence by an amount related to the frequency of occurrence of the thematic term within the document.

9. The processor implemented method of claim 8 prior to step a) further comprising the steps of:

e) receiving the value of the second number from an input device coupled to the processor.

10. The processor implemented method of claim 9 wherein the first number is at least three.