document: Quicklink selection for navigational query results Quicklinks for a website are navigational shortcuts displayed below the website homepage on a search results page , and that let the users directly jump to selected points inside the website . Since the real-estate on a search results page is constrained and valuable , picking the best set of quicklinks to maximize the benefits for a majority of the users becomes an important problem for search engines . Using user browsing trails obtained from browser toolbars , and a simple probabilistic model , we formulate the quicklink selection problem as a combinatorial optimizaton problem . We first demonstrate the hardness of the objective , and then propose an algorithm that is provably within a factor of 1-1 \/ e of the optimal . We also propose a different algorithm that works on trees and that can find the optimal solution ; unlike the previous algorithm , this algorithm can incorporate natural constraints on the set of chosen quicklinks . The efficacy of our methods is demonstrated via empirical results on both a manually labeled set of websites and a set for which quicklink click-through rates for several webpages were obtained from a real-world search engine .
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