Strategies as states

We define rationality and equilibrium when states specify agents’ actions and agents have arbitrary partitions over these states. Although some suggest that this natural modeling step leads to paradox, we show that Bayesian equilibrium is well defined and puzzles can be circumvented. The main problem arises when player j's partition informs j of i's move and i knows j's strategy. Then i's inference about j's move will vary with i's own move, and i may consequently play a dominated action. Plausible conditions on partitions rule out these scenarios. Equilibria exist under the same conditions, and more generally ε equilibria usually exist.     

Sequential selling mechanisms

Summary In this paper we attempt to formalize the idea that a mechanism that involves multilateral communication between buyers and sellers may be dominated by one that involves simple bilateral communication. To do this we consider the well known problem in which a seller tries to sell a single unit of output to a group ofN buyers who have independently distributed private valuations. Our arguments hinge on two considerations. First, buyers communicate their willingness to negotiate with the seller sequentially, and second, buyers have the option of purchasing the good from some alternative supplier. It is shown that the seller cannot improve upon a procedure in which she offers the good to each buyer in turn at a fixed price. The seller reverts to multilateral communication if possible, only when no buyer is willing to pay the fixed price. In reasonable environments buyers will be too impatient to wait for the outcome of a multilateral negotiation and all communications will be bilateral.In many problems in mechanism design, informed traders have no alternative to participation in the mechanism that is offered by its designer. The best mechanism from the designer's point of view is then the one that is most efficient at extracting informational rents, that is, a simple auction. In a competitive environment it is likely to be costly for buyers to participate in an auction or any other multilateral selling scheme in which the seller must process information from many different buyers because alternative trading opportunities will be disappearing during the time that the seller is collecting this information. Buyers might be willing to participate in an auction, but only if they could be guaranteed that the competition that they face will not eliminate too much of their surplus.At the other extreme to the auction is a simple fixed price selling scheme 1. The seller simply waits until he meets a buyer whose valuation is high enough, given the opportunities that exist in the rest of the market, for him to be willing to pay this price. The seller extracts the minimum of the buyer's informational rents since the price that a buyer pays is independent of his valuation. Yet the seller might like this scheme if adding a second bidder to the process makes it very difficult for him to find a buyer with a valuation high enough to want to participate.In the presence of opportunity costs, the seller faces a trade-off between his ability to extract buyers informational rents and his ability to find buyers who are willing to participate in any competitive process. In practice this trade-off will impose structure on the method that is used to determine a price. In markets where there are auctions, limits are put on buyer participation. In tobacco auctions bids are submitted at a distinct point in time from buyers who are present at that time. In real estate auctions time limits are put on the amount of time the seller will wait before making a decision. These restrictions on participation are presumably endogenously selected by the seller (possibly in competition with other mechanism designers) with this trade-off in mind.On the other hand, markets in which objects appear to trade at a fixed price are rarely so simple. A baker with a fixed supply of fresh bagels is unlikely to collect bids from buyers and award the bagels to the high bidder at the end of the day. Buyers are unlikely to be willing to participate in such a scheme since they can buy fresh bagels from a competitor down the street. Yet despite the fact that bagels sell at a fixed price throughout the day, most bakers are more than willing to let it be known that they will discount price at the end of the day on any bagels that they have not yet sold. Selling used cars presents a similar problem. Each potential buyer for the used car is likely to have inspected a number of alternatives, and is likely to know the prices at which these alternative can be obtained. A seller who suggests that buyers submit a bid, then wait until the seller is sure that no higher offer will be submitted is asking buyers to forgo these alternative opportunities with no gain to themselves. To avoid the rigidity of the pure fixed price scheme most used cars are sold for a fixed price or best offer. These examples suggest that the best selling mechanism may involve a complex interplay between participation and surplus extraction considerations.The purpose of this paper is to provide a simple formalism within which the factors that determine the best contract can be evaluated. We consider the best known environment from the point of view of auction design in which there are a large number of buyers with independent private valuations for a unit of an indivisible commodity that is being sold by a single supplier who acts as the mechanism designer. We modify this standard problem in two critical ways. First, we assume that the seller meets the potential buyers sequentially rather than all at once. Secondly we assume that buyers have a valuable alternative that yields them a sure surplus. This creates a simple bidding cost that is effectively the expected loss in surplus (created by the disappearance of outside alternatives) that the buyer faces during the time that he spends negotiating with the seller.These simple assumptions allow us to calculate the impact of competition and communication costs using completely standard arguments from the mechanism design literature. We are able to show that with these assumptions the seller's expected surplus will be highest if the object is sold according to the following modified fixed price scheme: the seller contacts each of the potential buyers in turn and either offers to negotiate or announces that he no longer wishes to trade. If he offers to negotiate and the buyer agrees, the buyer immediately has the option of trading for sure with the seller at a fixed price set ex ante. If the buyer does not wish to pay this fixed price, he may submit an alternative bid. The seller will then continue to contact new buyers, returning to trade with the buyer only if no buyer wishes to pay the fixed price and no higher bid is submitted.It will be clear that in our environment, both the simple fixed price scheme and the simple auction are feasible. The simple auction prevails when the fixed price is set equal to the maximum possible valuation, while the simple fixed price scheme occurs when the fixed price is set so that buyers are willing to participate if and only if they are willing to pay the fixed price. Our results will show that a simple auction in never optimal for the seller. The seller can always strictly improve his payoff by moving to a scheme in which there is some strictly positive probability that trade will occur at the fixed price. On the other hand, there are reasonable circumstances in which the seller cannot achieve a higher payoff than the one she gets by selling at a fixed price. It is shown that for any positive participation cost, there is a large, but finite, number of potential buyers so that the seller cannot achieve a higher payoff than what she gets by selling at a fixed price. Two simple, but important continuity results are also illustrated. As the cost of participation in the mechanism increases (decreases), the probability with which the seller's unit of output is sold at a fixed price goes to one (zero) in the best modified fixed price mechanism for the seller.Our paper is not the first to generate such a modified fixed price scheme. Both McAfee and McMillan (1988) and Riley and Zeckhauser (1983) come up with similar schemes for the case in which the seller must bear a fixed cost for each new buyer that she contacts. There are two essential differences between our model and theirs. First, as the cost is interpreted as the opportunity cost of participation in the mechanism, it is reasonable to imagine that the seller advertises the mechanism ex ante. Another way of putting this is that the seller pays a fixed rather than a variable cost to communicate the mechanism to buyers. This makes it possible to assume that the mechanism is common knowledge to the seller and all the buyers at the beginning of the communication process. For this reason we can make our case using completely standard arguments. Secondly, the mechanism in the opportunity cost case plays a different allocative role than it does in the case when the seller bears a cost. The mechanism must decide whether buyers should communicate with the seller or pursue their alternative activities, as well as who should trade and at what price. It is this allocative role that makes bilateral communication superior to multilateral communication in a competitive environment. These differences allow us to show, for example, that a simple fixed price scheme is undominated for the seller when the number of buyers is finite. As shown by McAfee and McMillan, this is only possible when the number of potential buyers is infinite when the seller bears the cost of communication.Remarkably, the existence of opportunity costs to buyer participation is not, by itself, sufficient to explain why sellers might prefer bilateral communications mechanisms. Samuelson (1983) and McAfee and McMillan (1987) show that when buyers must pay a fixed cost to submit a bid, which is equivalent to giving up a valuable alternative, a seller cannot expect to earn more than she does in a second price auction (though Samuelson shows that the reserve price may depend on the number of potential buyers). One of the contributions of this paper is to show that the assumption that buyers make their participation decisions simultaneously is critical to this result. Simultaneous entry decisions means that whether or not any particular buyer is assigned to the alternative activity is independent of any other buyer's valuation. With sequential communication the seller is able to relax this constraint. It is precisely the enlargement of the class of feasible mechanism that breaks down the optimality of the simple auction.The second author acknowledges the support of the Social Sciences and Humanities Research Council of Canada and the CRDE at the Université de Montreal.     

Endogenous hospital regulation and its effects on hospital and non-hospital expenditures

Past studies of hospital rate setting regulation conclude that mature programs have been effective in constraining hospital expenditures. However, if rate regulation is influenced by higher hospital expenditures the relationship between expenditures and rate setting is confounded. This study assesses the impact of rate setting on hospital and non-hospital expenditures using a simultaneous-equation model which separates the effects of hospital expenditures on the decision to regulate from the effects of regulation on expenditures. The simultaneous-equation results indicate that mature rate setting is associated with lower per capita health care expenditures, including hospital and non-hospital expenditures.     

Designing education for life on earth

Designing, viewed broadly as the human capacity to link thought and action, has meaning and value in the world that transcends its material associations. Given the nature and urgency of current socioeconomic and ecological problems, the creative, generative concept of design must be made more accessible and useful. Accordingly, my intent is to dispel prevailing, narrow, specialist impressions of design and to advance in the public mind a larger concept that can influence deliberations and behavior in society-at-large. One of today's most critical areas of need, and one where I think design can make a particularly significant contribution, is education. A critical task for such design-based education is enabling people to design an ecologically and economically sustainable future.     

Literacy,technology and ‘technological literacy’

The shortcomings of the technological literacy metaphor are reviewed. The lack of an agreed meaning for this concept reflects a widespread perplexity about how the study of technology should be incorporated into general education. The paper considers how the study of literature and history might contribute to an understanding of technology and posits a framework which permits the study of the made world to be incorporated within a humanistic educational scheme. It is suggested that the historical study of technologies of literacy could play a significant role in curricular integration.Based on a Plenary Address to the second Domains of Literacy Conference:Literacies for a Productive Future Institute of Education London 1/9/94Michael Barnett has been, since 1992, Professor of Technology and Education at the Institute of Education in London University. Prior to that he was Reader in Physics at Imperial College London. His main scholarly activities are concerned with the history, philosophy and sociology of technology and their bearing on educational practice. He has established an MA programme in Technology and Education which reflects these concerns.     

Transfer sciences: management of distributed knowledge production

This paper is concerned to develop the notion of transfer science to take account of what is perceived to be the emergence of a new mode of knowledge production. The new mode which is characterised by the production of knowledge in the context of application, by transdisciplinarity, by homogeneity and organisational diversity, by enhanced social accountability and reflexivity, and by new forms of quality control. The thrust of the new mode of knowledge production is to call into question conventional notions of knowledge transfer and focuses instead on the organisational and managerial implications of the emergence of a socially distributed knowledge production system. The paper concludes with a brief discussion of the policy implications of the emergence of the new mode of production. Needed in the new mode are science and technology policies which promote institutional permeability and policies which enable governments, acting through their civil service to act as brokers in the new knowledge production process. Such brokerage is necessary to enhance permeability between institutions within a particular country but also to increase co-operation and collaboration between institutions across countries.     

Portfolio Capital Flows: Hot or Cold?

A distinction is often made between short-term and long-termcapital flows: the former are deemed unstable hot money andthe latter are deemed stable cold money. Using time-series analysisof balance of payments data for five industrial and five developingcountries, we find that in most cases the labels "short-term"and "long-term" do not provide any information about the time-seriesproperties of the flow. In particular, long-term flows are oftenas volatile as short-term flows, and the time it takes for anunexpected shock to a flow to die out is similar across flows.long-term flows are also at least as unpredictable as short-termflows, and knowledge of the type of flow does not improve theability to forecast the aggregate capital account.     

The impact of tax on foreign direct investment: Empirical evidence and the implications for tax integration schemes

We estimate the impact of taxation on foreign direct investment (FDI) flows, using data on flows between seven countries for 1984 through 1989, and a sophisticated measure of the cost of capital. We find that the choice between domestic investment and total outward FDI is not significantly affected by taxation but that taxation does affect the location of outward FDI. These results are used to examine the impact of tax integration systems. Giving a tax credit to foreign shareholders may induce a large increase in inward FDI from exemption countries but not from partial-credit countries. For the United States, the total effect would be small.