How does a search engine company decide what ads to display with each query so as to maximize its revenue? This turns out to be a generalization of the online bipartite matching problem. We introduce the notion of a tradeoff revealing LP and use it to derive an optimal algorithm achieving a competitive ratio of 1 − 1/e for this problem.
Aranyak Mehta, Amin Saberi, Umesh V. Vazirani, Vij