1 : A method of ranking documents in a results list of documents in response to a search query comprising: retrieving previously stored input from a user regarding a relevance of one or more documents to the search query; discarding previous input by the user regarding the relevance of the one or more documents to the user; associating the user input with the search query and the document; determining a relevance formula having variables and parameters, the relevance formula for computing a relevance score for the document and the search query, wherein the variables comprise a plurality of features, and the parameters comprise a plurality of coefficients corresponding to each of the plurality of features; and applying the relevance formula to rank the document based on a relevance score, wherein the relevance score is dependent on the user input associated with the document and the search query.