Abstract: Different ad selection techniques may be evaluated and compared by (i) combining ads generated using at least two different techniques and (ii) determining performance statistics of these combined (e.g., interleaved) advertising serves over time. The relative performance of the different techniques can then be determined. These principles can also be used to gauge different ad scoring techniques. These principles can also be used to gauge different ad rendering techniques.

Abstract: A stopword detection component detects stopwords (also stop-phrases) in search queries input to keyword-based information retrieval systems. Potential stopwords are initially identified by comparing the terms in the search query to a list of known stopwords. Context data is then retrieved based on the search query and the identified stopwords. In one implementation, the context data includes documents retrieved from a document index. In another implementation, the context data includes categories relevant to the search query. Sets of retrieved context data are compared to one another to determine if they are substantially similar. If the sets of context data are substantially similar, this fact may be used to infer that the removal of the potential stopword(s) is not material to the search. If the sets of context data are not substantially similar, the potential stopword can be considered material to the search and should not be removed from the query.

Abstract: The present disclosure includes systems and techniques relating to ranking search results of a search query. In general, the subject matter described in this specification can be embodied in a computer-implemented method that includes determining a measure of relevance for a document result within a context of a search query for which the document result is returned, the determining being based on a first number in relation to a second number, the first number corresponding to longer views of the document result, and the second number corresponding to at least shorter views of the document result; and outputting the measure of relevance to a ranking engine for ranking of search results, including the document result, for a new search corresponding to the search query. The subject matter described in this specification can also be embodied in various corresponding computer program products, apparatus and systems.

Abstract: The subject matter of this specification can be implemented in, among other things, a computer-implemented method including determining an affinity score representing an affinity of a user with respect to a contact of the user, wherein the affinity score is an indication of a strength of a relationship between the user and the contact, determining an engagement score of the user with respect to the contact, wherein the engagement score in an indication of a probability of the user engaging with a content item associated with the contact, determining an interest score of the user with respect to the contact based on the affinity score and the engagement score and providing a plurality of content items posted by the contact display in an activity stream, the content items being ordered based on the interest score. Other aspects can include corresponding systems, apparatus and computer program products.

Abstract: A system receives a search query from a user and searches a group of repositories, based on the search query, to identify, for each of the repositories, a set of search results. The system also identifies one of the repositories based on a likelihood that the user desires information from the identified repository and presents the set of search results associated with the identified repository.

Abstract: In one aspect, the present disclosure can be embodied in a method that includes identifying a collection of entities from one or more data sources, calculating a score for subsets of entities from the collection based on one or more seed entities associated with the collection, identifying one or more entities from each of the subsets based on the calculated score, assigning the calculated score to the identified one or more entities from the respective subset, and ranking the one or more entities based on the assigned score, so as to identify entities in the collection that are related to the one or more seed entities.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for reranking query completions based on activity session data. One of the methods includes receiving a query prefix from a user. Query completions are obtained for the query prefix. One or more likely queries that are likely to co-occur with a reference query in user activity sessions are obtained. If one of the likely queries matches one of the query completions, a modified ranking of the query completions is determined, including boosting a ranking of matching query completions. The modified ranking of the query completions is provided in response to receiving the query prefix.

Abstract: Methods and systems allow users to enter natural language terms that describe a particular web site into an address field of a browser instead of a formal URL. The terms are evaluated to determine whether they correspond, with a high likelihood, to a particular web site. If so, this web site may be immediately accessed. If not, a list of search results based on the terms may be displayed by the browser.

Abstract: Methods and systems allow users to enter natural language terms that describe a particular web site into an address field of a browser instead of a formal URL. The terms are evaluated to determine whether they correspond, with a high likelihood, to a particular web site. If so, this web site may be immediately accessed. If not, a list of search results based on the terms may be displayed by the browser.

Abstract: The present disclosure includes systems and techniques relating to ranking search results of a search query. In general, the subject matter described in this specification can be embodied in a computer-implemented method that includes determining a measure of relevance for a document result within a context of a search query for which the document result is returned, the determining being based on a first number in relation to a second number, the first number corresponding to longer views of the document result, and the second number corresponding to at least shorter views of the document result; and outputting the measure of relevance to a ranking engine for ranking of search results, including the document result, for a new search corresponding to the search query. The subject matter described in this specification can also be embodied in various corresponding computer program products, apparatus and systems.

Abstract: Methods and systems for improved searching are described. In one of the described methods, a user enters a search query, and in response, a search engine receives a substantially complete initial search result set having a plurality of ranked article identifiers. The search engine automatically selects at least one of the article identifiers and provides a final result set in which the selected article identifier is ranked higher than in the initial search result set.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for ranking images using hover data. In one aspect, a method includes determining a click count and a hover count for an image and a search query pair. The click count specifies a number of times that an image search result that includes a representation of the image has been selected when provided in response to the search query. The hover count specifies a number of times that the representation of the image has been hovered over when the image search result has been provided in response to the search query. A quality measure for the image with respect to the search query is determined. The quality measure is based on the click count and the hover count. A ranking of the image is adjusted for the search query based on the quality measure for the image.

Abstract: A system receives a search query from a user and searches a group of repositories, based on the search query, to identify, for each of the repositories, a set of search results. The system also identifies one of the repositories based on a likelihood that the user desires information from the identified repository and presents the set of search results associated with the identified repository.

Abstract: A search engine includes a decision component that determines whether documents that are returned in response to a user search query are likely to be very relevant to the search query. Links that refer to documents that the search engine determines to likely be very relevant may be displayed with visual cues that assist the user in browsing the links. The decision component may base its decision on a number of parameters, including: (1) the position of the document in a ranked list of search results, (2) the click through rate of the document, (3) relevance scores for the document and other documents that are returned as hits in response to the search query, and (4) whether the document is classified as a pornographic document (the search engine may refrain from showing visual cues for potentially pornographic documents).

Abstract: A system and method for providing preferred language and/or country ordering of search results is described. A search query describing potentially retrievable information provided in a plurality of search result languages and/or countries is received. A search is executed by evaluating the search query against information characteristics maintained in a searchable data repository. At least one preferred language and/or country applicable to search results generated is dynamically determined responsive to the executed search. At least some of the search results are ordered in consideration of the at least one preferred language and/or country.

Abstract: A system ranks documents based, at least in part, on a ranking model. The ranking model may be generated to predict the likelihood that a document will be selected. The system may receive a search query and identify documents relating to the search query. The system may then rank the documents based, at least in part, on the ranking model and form search results for the search query from the ranked documents.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage medium, for identifying a set of items of digital content displayed to a user; processing the set of items to identify a set of boost items, items within the set of boost items to be prominently displayed, processing comprising: receiving a close-ties score associated with a respective item, the close-ties score representing a relationship between the user and other users associated with the respective item and an importance of a social circle associated with the item to the user, determining that the close-ties score associated with the respective item exceeds a threshold close-ties score, and in response to determining that the close-ties score exceeds the threshold close-ties score, adding the respective item to the set of boost items; providing instructions for boosting a display of items in the set of boost items in a page displayed to the user.

Abstract: A system receives a search query from a user and searches a group of repositories, based on the search query, to identify, for each of the repositories, a set of search results. The system also identifies one of the repositories based on a likelihood that the user desires information from the identified repository and presents the set of search results associated with the identified repository.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for reranking query completions based on activity session data. One of the methods includes receiving a query prefix from a user. Query completions are obtained for the query prefix. One or more likely queries that are likely to co-occur with a reference query in user activity sessions are obtained. If one of the likely queries matches one of the query completions, a modified ranking of the query completions is determined, including boosting a ranking of matching query completions. The modified ranking of the query completions is provided in response to receiving the query prefix.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for ranking images using hover data. In one aspect, a method includes determining a click count and a hover count for an image and a search query pair. The click count specifies a number of times that an image search result that includes a representation of the image has been selected when provided in response to the search query. The hover count specifies a number of times that the representation of the image has been hovered over when the image search result has been provided in response to the search query. A quality measure for the image with respect to the search query is determined. The quality measure is based on the click count and the hover count. A ranking of the image is adjusted for the search query based on the quality measure for the image.