Synonyms are the foundation of the concept understanding work that Google is carrying on. We can see shallowly how it works in the Synonyms search tool based on its index. The search engine gives you back results related with what you want, which means that considers the intention rather than only the keywords.
If the meaning of the query is the same, you should get the same results no matter how you phrase your question. (Google Blog)
Understanding is three-pronged:
U. of pages: associating important concepts to a page even when they are not obvious on the page.
U. of queries: beyond just the few words in the user’s query. Good implications:
- Not having to think in all the posible words that covers your key concept.
- Not having to develop shortened words. For example: Dr. Zhivago (it knows Dr is for Doctor) or LC stands for Library of Congress.
- More natural and flexible querying.
- Higher relevance.
U. of users
Does it solve not knowing the right word?
Regarding concept identification:
Another technology we use in our ranking system is concept identification. Identifying critical concepts in the query allows us to return much more relevant results. For example, our algorithms understand that in the query [new york times square church] the user is looking for the well-known church in Times Square and not for articles from the New York Times. We don’t just stop at identifying concepts; we further enhance the query with the right concepts when, for instance, someone looking for [PC and its impact on people] is in fact looking for impact of computers on society, or someone who searches for [rainforest instructional activities for vocabulary] is really looking for rain forest lesson plans. Our query analysis algorithms have many such state-of-the-art techniques built into them, and once again, we do this internationally in almost every language we serve. (from Google Blog)
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