When Does Google Display Alternative Titles and Descriptions?

Many times we see alternative titles and descriptions presented by Google in the search results because algorithms predict those descriptions to be more relevant with respect to the search query. A document retrieval system generates these alternative snippets based on the analysis of the location of the query terms in the web page.

How Does Google Identifies the Best Snippet?

Google Snippets

Google identifies the best snippet based on the following 2 factors:-

Factor 1

1- Identifying paragraphs based on the search query and generating a snippet based on the calculated distances of the identified paragraphs.

2- Paragraph identification is based on a score depending on the length of the paragraph and the distances of the paragraph.

3- After the paragraph gets selected, a snippet is generated comprising a number of predetermined characters of the selected paragraph.

Factor 2

1- Identifying paragraphs based on the search query and generating a snippet based on the location of the query terms within the document.

Full Patent information can be viewed here:- 

Generation of document snippets based on queries and search results  

	Inventors: Verstak; Alexandre A. (Cupertino, CA), Acharya; Anurag (Campbell, CA)	Assignee: Google Inc. (Mountain View, CA)	Family ID: 45841943	Appl. No.: 11/282,560	Filed: November 18, 2005

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