RANKING SEARCH RESULTS USING AUTHOR EXTRACTION

• US 20090182723A1
• Filed: 01/10/2008
• Published: 07/16/2009
• Est. Priority Date: 01/10/2008
• Status: Abandoned Application

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Meyerzon, Dmitriy, Li, Hang, Shnitko, Yauhen, Hu, Yunhua
• Application Number:
  US11/972,613
• Publication Number:
  US 20090182723A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/38 Retrieval characterised by using metadata, e.g. metadata not derived from the content or metadata generated manually

Abstract

Architecture that extracts author information from general documents and uses the author information for search results ranking. The architecture performs automatic author value extraction and makes the extracted value available at index time for subsequent use at query processing and results ranking. Machine learning (e.g., a perceptron algorithm) is employed and a set of input features for the perceptron algorithm utilized for author value extraction. The extracted author value is converted into a feature for input a ranking function for generating a ranking score for each document. The input features can also be weighted according to weighting criteria.

Claims

1. A computer-implemented ranking system, comprising:

an extraction component for extracting author information from documents returned as results of a search; and

a ranking component for ranking the documents based in part on the author information.

2. The system of claim 1, wherein the extracted author information is made available at index time for queries and ranking of the documents.

3. The system of claim 1, wherein the extracted author information is metadata associated with the documents.

4. The system of claim 1, wherein the extracted author information is obtained from content of the documents.

5. The system of claim 1, further comprising a machine learning algorithm for extracting the author information from the documents.

6. The system of claim 5, wherein the machine learning algorithm is based on a perceptron model.

7. The system of claim 6, wherein the perceptron model is an author extraction perceptron that employs input features which include one or more of author name, positive word, negative word, character count, average word count, period mark, or end-with mark.

8. The system of claim 1, further comprising a rules component for focusing extraction on a particular unit of the documents.

9. The system of claim 1, wherein the author information is an input feature to the ranking component, the ranking component based on a variant of a BM25 ranking function, the variant defined by:

$\sum <br><br>\frac{{\mathrm{tf}}^{<br><br>\mathrm{\prime <br><br>}}<br><br>\left(k_1+1\right)}{k_1+{\mathrm{tf}}^{<br><br>\mathrm{\prime <br><br>}}}\times <br><br>\log \left(\frac{N}{n}\right)$ ${\mathrm{tf}}_t^{<br><br>\mathrm{\prime <br><br>}}=\underset{p\in <br><br>D}{\sum <br><br>}<br><br>{\mathrm{tf}}_{t,p}·<br><br>w_p·<br><br>\frac{1}{\left(1-b\right)+b<br><br>\left(\frac{{\mathrm{DL}}_p}{{\mathrm{AVDL}}_p}\right)}$

where, the tf_t,p is a term frequency for term t in property p, DL_p is a length of property p, AVDL_p is an average property length of document D, w is a property weight, k₁ is a tunable parameter, N is the number of documents in a corpora, b is a free parameter for controlling document length normalization, and n is the number of documents containing the term t.

10. A computer-implemented ranking system, comprising:

an extraction component that employs a machine learning algorithm for extracting author information from a general document returned in results of a search; and

a ranking component for ranking the general document among the document results based on a ranking function that receives author-related input features to output a document score.

11. The system of claim 10, further comprising a rules component for focusing extraction to a unit of the document based on one or more rules.

12. The system of claim 10, wherein the author-related input features are weighted.

13. The system of claim 10, wherein the author information is extracted from the document body or the document metadata.

14. A computer-implemented method of ranking search results, comprising:

extracting author information from a document returned in results of a search;

inputting the author information into ranking function;

computing a document ranking score; and

ranking the document relative to the results based on the author information.

15. The method of claim 14, further comprising extracting the author information using a classifier based on a perceptron model.

16. The method of claim 15, further comprising finding author candidates for the author information using a name list as an input to the model.

17. The method of claim 14, further comprising testing for the author information in a candidate unit using characters patterns.

18. The method of claim 14, further comprising generating a feature list for input to a perceptron algorithm, the feature list includes one or more of a name list, positive words, negative words, period mark, character count, average word count, and end-with mark.

19. The method of claim 14, further comprising identifying units of the document that contain the author information using a classifier.

20. The method of claim 14, further comprising associating the author information with the document at index time.