1. A method for classifying search results by a search engine comprising an index of documents in a memory corresponding to a plurality of products offered by a plurality of online shopping sites and comprising text classifiers and image classifiers, a user interface enabling for enabling a user to browse products offerings organized according to the product taxonomy and receiving a search query from the user and providing the user with a set of search results, and a ranking engine for ranking the set of search results to enhance the user's experience, the method comprising: inferring a first distribution on a set of training data using a first classifier; inferring a second distribution on the set of training data using a second classifier; concatenating the first distribution and the second distribution; classifying each search result among a set of search results based on the concatenation; and ranking the search results based at least in part on the classification.