document: Spatial variation in search engine queries Local aspects of Web search - associating Web content and queries with geography - is a topic of growing interest . However , the underlying question of how spatial variation is manifested in search queries is still not well understood . Here we develop a probabilistic framework for quantifying such spatial variation ; on complete Yahoo ! query logs , we find that our model is able to localize large classes of queries to within a few miles of their natural centers based only on the distribution of activity for the query . Our model provides not only an estimate of a query 's geographic center , but also a measure of its spatial dispersion , indicating whether it has highly local interest or broader regional or national appeal . We also show how variations on our model can track geographically shifting topics over time , annotate a map with each location 's `` distinctive queries '' , and delineate the `` spheres of influence '' for competing queries in the same general domain .
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