165 research outputs found
Adoption of Standards under Uncertainty
The presence of noise in compliance times may have a critical impact on the selection of new technological standards. A technically superior standard is not necessarily viable because an arbitrarily small amount of noise may render coordination on that standard impossible. The criterion for the viability of a standard is that the sum of \support ratios" of all players must be smaller than one, where \support ratio" is dened as the ratio of the rm's per-period cost of supporting the standard to the per-period gross benet that the rm receives after all players comply with the standard.
Coordination under Uncertainty
A decision maker needs to schedule several activities that take uncertain time to complete and are only valuable together. Some activities are bound to be finished earlier than others, thus incurring waiting costs. We show how to schedule activities optimally, how to give independent agents performing them incentives that implement the efficient schedule, how to form teams, and how to optimally reduce uncertainty when it is possible to do so at a cost. The paper offers insights into important economic decisions such as planning large projects and coordinating product development activities.
Internet Advertising and the Generalized Second Price Auction: Selling Billions of Dollars Worth of Keywords
We investigate the "generalized second price" auction (GSP), a new mechanism which is used by search engines to sell online advertising that most Internet users encounter daily. GSP is tailored to its unique environment, and neither the mechanism nor the environment have previously been studied in the mechanism design literature. Although GSP looks similar to the Vickrey-Clarke-Groves (VCG) mechanism, its properties are very different. In particular, unlike the VCG mechanism, GSP generally does not have an equilibrium in dominant strategies, and truth-telling is not an equilibrium of GSP. To analyze the properties of GSP in a dynamic environment, we describe the generalized English auction that corresponds to the GSP and show that it has a unique equilibrium. This is an ex post equilibrium that results in the same payoffs to all players as the dominant strategy equilibrium of VCG.
Simple Estimators for the Parameters of Discrete Dynamic Games (with Entry/Exit Samples)
This paper considers the problem of estimating the distribution of payoffs in a discrete dynamic game, focusing on models where the goal is to learn about the distribution of firms' entry and exit costs. The idea is to begin with non parametric first stage estimates of entry and continuation values obtained by computing sample averages of the realized continuation values of entrants who do enter and incumbents who do continue. Under certain assumptions these values are linear functions of the parameters of the problem, and hence are not computationally burdensome to use. Attention is given to the small sample problem of estimation error in the non parametric estimates and this leads to a preference for use of particularly simple estimates of continuation values and moments.
Simple Estimators for the Parameters of Discrete Dynamic Games (with Entry/Exit Examples)
This paper considers the problem of estimating the distribution of payoffs in a discrete dynamic game, focusing on models where the goal is to learn about the distribution of firms' entry and exit costs. The idea is to begin with non parametric first stage etimates of entry and continuation values obtained by computing sample averages of the realized continuation values of entrants who do enter and incumbents who do continue. Under certain assumptions these values are linear functions of the parameters of the problem, and hence are not computationally burdensome to use. Attention is given to the small sample problem of estimation error in the non parametric estimates and this leads to a preference for use of particularly simple estimates of continuation values and moments.
Information Disclosure and Unraveling in Matching Markets
This paper explores information disclosure in matching markets, e.g., the informativeness of transcripts given out by universities. We show that the same, "benchmark," amount of information is disclosed in essentially all equilibria. We then demonstrate that if universities disclose the benchmark amount of information, students and employers will not find it profitable to contract early; if they disclose more, unraveling will occur.
AMS Without 4-Wise Independence on Product Domains
In their seminal work, Alon, Matias, and Szegedy introduced several sketching
techniques, including showing that 4-wise independence is sufficient to obtain
good approximations of the second frequency moment. In this work, we show that
their sketching technique can be extended to product domains by using
the product of 4-wise independent functions on . Our work extends that of
Indyk and McGregor, who showed the result for . Their primary motivation
was the problem of identifying correlations in data streams. In their model, a
stream of pairs arrive, giving a joint distribution ,
and they find approximation algorithms for how close the joint distribution is
to the product of the marginal distributions under various metrics, which
naturally corresponds to how close and are to being independent. By
using our technique, we obtain a new result for the problem of approximating
the distance between the joint distribution and the product of the
marginal distributions for -ary vectors, instead of just pairs, in a single
pass. Our analysis gives a randomized algorithm that is a
approximation (with probability ) that requires space logarithmic in
and and proportional to
The Leading Edge Accelerating change: Fostering innovation in healthcare delivery at academic medical centers
a b s t r a c t Academic medical centers (AMCs) have the potential to be leaders in the era of healthcare delivery reform, but most have yet to display a commitment to delivery innovation on par with their commitment to basic research. Several institutional factors impede delivery innovation including the paucity of adequate training in design and implementation of new delivery models and the lack of established pathways for academic career advancement outside of research. This paper proposes two initiatives to jumpstart disruptive innovation at AMCs: an institutional "innovation incubator" program and a clinician-innovator career track coupled with innovation training programs
Information Aggregation in Exponential Family Markets
We consider the design of prediction market mechanisms known as automated
market makers. We show that we can design these mechanisms via the mold of
\emph{exponential family distributions}, a popular and well-studied probability
distribution template used in statistics. We give a full development of this
relationship and explore a range of benefits. We draw connections between the
information aggregation of market prices and the belief aggregation of learning
agents that rely on exponential family distributions. We develop a very natural
analysis of the market behavior as well as the price equilibrium under the
assumption that the traders exhibit risk aversion according to exponential
utility. We also consider similar aspects under alternative models, such as
when traders are budget constrained
Discovery and quantification of a widespread methane ebullition event in a coastal inlet (Baltic Sea) using a novel sonar strategy
How much of the greenhouse gas methane is transported from the seafloor to the atmosphere is unclear. Here, we present data describing an extensive ebullition event that occurred in Eckernförde Bay, a shallow gas-hosting coastal inlet in the Baltic Sea, in the fall of 2014. A weak storm induced hydrostatic pressure fluctuations that in turn stimulated gas ebullition from the seabed. In a finely tuned sonar survey of the bay, we obtained a hydroacoustic dataset with exceptionally high sensitivity for bubble detection. This allowed us to identify 2849 bubble seeps rising within 28 h from the seafloor across the 90 km² study site. Based on our calculations, the estimated bubble-driven episodic methane flux from the seafloor across the bay is 1,900 μMol m-2 d-1. Our study demonstrates that storm-associated fluctuations of hydrostatic pressure induce bulk gas-driven ebullitions. Given the extensive occurrence of shallow gas-hosting sediments in coastal seas, similar ebullition events probably take place in many parts of the Western Baltic Sea. However, these are likely to be missed during field investigations, due to the lack of high-quality data acquisition during storms, such that atmospheric inputs of marine-derived methane will be highly underestimated
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