Allocative and Informational Externalities in Auctions and Related Mechanisms

We study the effects of allocative and informational externalities in (multi-object) auctions and related mechanisms. Such externalities naturally arise in models that embed auctions in larger economic contexts. In particular, they appear when there is downstream interaction among bidders after the auction has closed. The endogeneity of valuations is the main driving force behind many new, specific phenomena with allocative externalities: even in complete information settings, traditional auction formats need not be efficient, and they may give rise to multiple equilibria and strategic non-participation. But, in the absence of informational externalities, welfare maximization can be achieved by Vickrey-Clarke- Groves mechanisms. Welfare-maximizing Bayes-Nash implementation is, however, impossible in multi-object settings with informational externalities, unless the allocation problem is separable across objects (e.g. there are no allocative externalities nor complementarities) or signals are one-dimensional. Moreover, implementation of any choice function via ex-post equilibrium is generically impossible with informational externalities and multidimensional types. A theory of information constraints with multidimensional signals is rather complex, but indispensable for our study

Auctioning Bulk Mobile Messages

The search for enablers of continued growth of SMS traffic, as well asthe take-off of the more diversified MMS message contents, open up forenterprises the potential of bulk use of mobile messaging , instead ofessentially one-by-one use. In parallel, such enterprises or valueadded services needing mobile messaging in bulk - for spot use or foruse over a prescribed period of time - want to minimize totalacquisition costs, from a set of technically approved providers ofmessaging capacity.This leads naturally to the evaluation of auctioning for bulk SMS orMMS messaging capacity, with the intrinsic advantages therein such asreduction in acquisition costs, allocation efficiency, and optimality.The paper shows, with extensive results as evidence from simulationscarried out in the Rotterdam School of Management e-Auction room, howmulti-attribute reverse auctions perform for the enterprise-buyer, aswell as for the messaging capacity-sellers. We compare 1- and 5-roundauctions, to show the learning effect and the benefits thereof to thevarious parties. The sensitivity will be reported to changes in theenterprise's and the capacity providers utilities and prioritiesbetween message attributes (such as price, size, security, anddelivery delay). At the organizational level, the paper also considersalternate organizational deployment schemes and properties for anoff-line or spot bulk messaging capacity market, subject to technicaland regulatory constraints.MMS;EMS;Mobile commerce;SMS;multi-attribute auctions

A Double-Sided Multiunit Combinatorial Auction for Substitutes: Theory and Algorithms

Combinatorial exchanges have existed for a long time in securities markets. In these auctions buyers and sellers can place orders on combinations, or bundles of different securities. These orders are conjunctive: they are matched only if the full bundle is available. On business-to-business (B2B) exchanges, buyers have the choice to receive the same product with different attributes; for instance the same product can be produced by different sellers. A buyer indicates his preference by submitting a disjunctive order, where he specifies how much of the product he wants, and how much he values each attribute. Only the goods with the best attributes and prices will be matched. This article considers a doubled-sided multi-unit combinatorial auction for substitutes, that is, a uniform price auction where buyers and sellers place both types of orders, conjunctive and disjunctive. We prove the existence of a linear price which is both competitive and surplus-maximizing when goods are perfectly divisible, and nearly so otherwise. We describe an algorithm to clear the market, which is particularly efficient when the number of traders is large.Combinatorial auction, economic equilibrium

Property Rights Conservation and Development: An Analysis of Extractive Reserves in the Brazilian Amazon

The economic literature of property rights has been assessing the impact of different community based arrangements on the efficiency of natural resource management of specific areas. Differently, other strands of development economics and policy-oriented research have been concerned with issues such as poverty alleviation, technological progress and the capability to compete in market economies, which go beyond the local areas where traditional communities live and include the wider economy. The extractive reserves in the Brazilian Amazon offer perhaps one of the most interesting cases for investigating the connections between these two approaches in the context of tropical forests. It is based on the idea that the combination of public property with collective use in particular forest areas can generate competitive and, at the same time, sustainable exploitation of its natural resources. This paper aims to analyse whether the existing property rights support the joint objective of conservation and development. Our main result is that current property rights systems are efficient only with respect to competition in markets for existing extractive products. This finding points out to a fundamental contradiction between the static structure of the property rights systems and the dynamic nature of two most promising development paths, namely the discovery of new products and the supply of biological inputs for plantations. The current model of extractive reserves based on the design of internal property rights fails to taken into account the broader economic context where the reserves must generate a viable revenue stream. We conclude therefore that under the current set of institutions, the development objectives inherent in the extractive reserves model are likely to face probably considerable challenges to be accomplished in the future.Property rights, Extractive reserves, Environment and Development

Allocation in Practice

How do we allocate scarcere sources? How do we fairly allocate costs? These are two pressing challenges facing society today. I discuss two recent projects at NICTA concerning resource and cost allocation. In the first, we have been working with FoodBank Local, a social startup working in collaboration with food bank charities around the world to optimise the logistics of collecting and distributing donated food. Before we can distribute this food, we must decide how to allocate it to different charities and food kitchens. This gives rise to a fair division problem with several new dimensions, rarely considered in the literature. In the second, we have been looking at cost allocation within the distribution network of a large multinational company. This also has several new dimensions rarely considered in the literature.Comment: To appear in Proc. of 37th edition of the German Conference on Artificial Intelligence (KI 2014), Springer LNC

Bounding the Optimal Revenue of Selling Multiple Goods

Using duality theory techniques we derive simple, closed-form formulas for bounding the optimal revenue of a monopolist selling many heterogeneous goods, in the case where the buyer's valuations for the items come i.i.d. from a uniform distribution and in the case where they follow independent (but not necessarily identical) exponential distributions. We apply this in order to get in both these settings specific performance guarantees, as functions of the number of items $m$, for the simple deterministic selling mechanisms studied by Hart and Nisan [EC 2012], namely the one that sells the items separately and the one that offers them all in a single bundle. We also propose and study the performance of a natural randomized mechanism for exponential valuations, called Proportional. As an interesting corollary, for the special case where the exponential distributions are also identical, we can derive that offering the goods in a single full bundle is the optimal selling mechanism for any number of items. To our knowledge, this is the first result of its kind: finding a revenue-maximizing auction in an additive setting with arbitrarily many goods

Market Design, Bidding Rules, and Long Memory in Electricity Prices

In uniform price, sealed-bid day-ahead electricity auctions, the market price is set at the intersection between aggregate demand and supply functions built by a market operator. Each day, just one agent - the marginal generator - owns the market-clearing plant. Day-ahead auctions are moreover embedded in multi-segment systems, wherein diverse protocols coexist and change over time. Such a complex environment leads to adoption of simple, adaptive bidding rules. Specifically, such a market design lets two different types of routines emerge, depending on whether the agent is a likely marginal or inframarginal generator. However, because of the uniform price mechanism, only the bidding behavior of the former can be reflected into market prices. Depending on the specific way marginal generators process past information to set their bids - 'hyperbolic' or 'exponential' - electricity prices are likely to display long- or short-memory. Experimental evidence on hyperbolic discounting - a quite robust behavioral bias in humans - supports a long-memory view of electricity prices. This insight is broadly confirmed by spectral analysis of daily data from NordPool and CalPX markets, in sharp contrast with most previous empirical studies. This paper underlines the importance of institutional settings in determining market outcomes, and an interesting mapping of bidding rules and models of information processing into the time series properties of market prices.Market Design, Electricity Markets, Hyperbolic Discounting, Long Memory, Fractional Processes