Patent ID: 8195674

Claim:
A computer-implemented method, comprising: generating, by one or more server devices, a model that is based on: a condition that includes a conjunction of a plurality of features associated with documents, and statistics, received from one or more other devices, associated with the condition, where a particular statistic from a particular device, of the one or more other devices, indicates a weight, determined by the particular device, for the condition, generating the model including: generating a new weight for the condition, for use in the model, based on the received statistics from the one or more other devices, the new weight for the condition indicating how relevant the condition is, with respect to other conditions in the model, in determining how relevant a document is to a search query, generating a candidate rule for the model based on the condition and the received statistics, determining whether to add the candidate rule to the model, and upon determining that the candidate rule should not be added to the model, setting a weight, for the rule, to a value that indicates that the candidate rule should not be added to the model; and using, by the one or more server devices, the model to generate a rank for a document, the rank indicating an estimated probability that the document is relevant to a received search query.