Christopher A. Wilkens

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We present algorithms for a class of resource allocation problems both in the online setting with stochastic input and in the offline setting. This class of problems contains many interesting special cases such as the Adwords problem. In the online setting we introduce a new distributional model called the adversarial stochastic input model, which is a(More)
Truthfulness is fragile and demanding. It is oftentimes harder to guarantee truthfulness when solving a problem than it is to solve the problem itself. Even worse, truthfulness can be utterly destroyed by small uncertainties in a mechanism’s outcome. One obstacle is that truthful payments depend on outcomes other than the one realized, such as the(More)
The first-price auction is popular in practice for its simplicity and transparency. Moreover, its potential virtues grow in complex settings where incentive compatible auctions may generate little or no revenue. Unfortunately, the first-price auction is poorly understood in theory because equilibrium is not <i>a priori</i> a credible predictor of bidder(More)
The convexity assumptions required for the Arrow-Debreu theorem are reasonable and realistic for preferences; however, they are highly problematic for production because they rule out economies of scale. We take a complexity-theoretic look at economies with non-convex production. It is known that in such markets equilibrium prices may not exist; we show(More)
Bidders often want to get as much as they can without violating constraints on what they spend. For example , advertisers seek to maximize the impressions, clicks, sales, or market share generated by their advertising , subject to budget or return-on-investment (ROI) constraints. Likewise, when bidders have no direct utility for leftover money – e.g.,(More)
The popular generalized second price (GSP) auction for sponsored search is built upon a separable model of click-through-rates that decomposes the likelihood of a click into the product of a " slot effect " and an " advertiser effect " —if the first slot is twice as good as the second for some bidder, then it is twice as good for everyone. Though appealing(More)