Tacit Collusion in a Spatial Model with Delivered Pricing

Received August 5, 1999; revised version received July 20, 2001     

Analysis of Hybrid Life-tests in Presence of Competing Risks

The mixture of type-I and type-II censoring schemes, called the hybrid censoring scheme is quite common in life-testing or reliability experiments. In this paper, we consider the competing risks model in presence of hybrid censored data. Under this set up, it is assumed that the item may fail due to various causes and the corresponding lifetime distributions are independent and exponentially distributed with different scale parameters. We obtain the maximum likelihood estimators of the mean life of the different causes and derive their exact distributions. Using the exact distributions, all the moments can be obtained. Asymptotic confidence intervals and two bootstrap confidence intervals are also proposed. Bayes estimates and credible intervals of the unknown parameters are obtained under the assumptions of independent inverted gamma priors of the mean life of the different causes. Different methods have been compared using Monte Carlo simulations. Onereal data set has been analyzed for illustrative purposes. Part of the work was supported by a grant from the Natural Sciences and Engineering Research Council.     

On estimating market efficiency

In this paper, we discuss commentaries by Maynes and Hjorth-Andersen on our earlier paper (1990), and then go on to discuss the merits of various measures of market efficiency which have appeared in the literature. While Maynes criticized the model in our 1990 paper for a lack of realism, we argue that our limited objective of demonstrating that price-quality correlations are not necessarily related to market efficiency did not require a model which was realistic in all details. We also demonstrate that our basic conclusion that the price-quality correlation need not measure market efficiency does not depend on our theoretical model. Hjorth-Andersen advanced a number of alternative reasons why price-quality correlations may not measure efficiency, and we view his arguments largely as complementary to ours. The basic conclusion is that there are severe problems with interpreting measured price-quality correlations as measures of efficiency. We go on to discuss alternative measures. While no alternatives are completely satisfactory, we argue that measures based on deviations from an efficient frontier have some attractive properties, and are currently the most desirable alternative.

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Zur bestimmung der effizienz von mÄrkten

Zusammenfassung Die Autoren gehen in diesem Beitrag auf die Kommentare von Maynes (1992) und Hjorth-Andersen (1992) zu ihrem früheren Beitrag in dieser Zeitschrift (1990) ein und diskutieren dann die verschiedenen Indikatoren der Markteffizienz, die in der Literatur vorgeschlagen wurden. WÄhrend Maynes das Modell des früheren Beitrages der Autoren wegen zu geringer RealitÄtsnahe kritisierte, halten die Autoren jetzt dagegen, da\ für das begrenzte Ziel jenes Beitrages, nÄmlich zu zeigen, da\ Preis-QualitÄts-Korrelationen nicht notwendigerweise mit Marktef-fizienz verknüpft sind, Wirklichkeitstreue in allen Details gar nicht erforderlich ist. Sie zeigen darüber hinaus, da\ ihre grundlegende Schlu\folgerung, da\ Preis-QualitÄts-Korrelationen nicht ein Ma\ der Markteffizienz sein müssen, von ihrem theoretischen Modell nicht einmal abhÄngt. Hjorth-Andersen führt eine Reihe weiterer Gründe an, deretwegen Preis-QualitÄts-Korrelationen keine Indikatoren für Effizienz sein mögen, die von den Autoren als ErgÄnzung der eigenen überlegungen angesehen werden. Das Hauptergebnis des vorliegenden Beitrages ist folglich, da\ es ernste Probleme bei der Interpretation solcher Korrelationen als Effizienz-Ma\e gibt. Sie diskutieren deshalb andere Indikatoren, von denen allerdings keiner vollstÄndig befriedigend ist. Allerdings dürften Ma\e, die die Abweichung von einer Grenzlinie günstigster EinkÄufe erfassen, zur Zeit die aussichtsreichste Möglichkeit sein.

     

Preference aggregation and repeat buying in households

Marketing researchers have long used brand switching analyses and Markov transition matrices to gain insights into managerial problems. Almost without exception, this work makes (inappropriate) inferences about individual consumers by analyzing household-level data. This paper presents a procedure based on the distribution of run lengths in household level panel data that allows more insights into the choice behavior of the individuals in the household. We test these procedures in a large simulation study by attempting to recover the underlying (known) structure of the process generating a string of panel data. Finally, we use the procedure to classify the purchase behavior, with respect to powdered soft drinks, of a set of households in a panel. Our results show that marketing scientists have the potential to learn and test more hypotheses about the individuals in a household by examining the distribution of run lengths.We gratefully acknowledge Professor Bari Harlam of the University of Rhode Island for providing the panel data.     

Deal Size,Bid Premium,and Gains in Bank Mergers: The Impact of Managerial Motivations

Do mergers with greater target relative to acquirer size create more value than mergers with smaller relative sized targets? Do larger bid amounts represent wealth transfers from acquirers or do they signal greater expected merger gains? We hypothesize that the relations among aggregate merger gains, relative size, and bid premiums are asymmetric across mergers made by value‐enhancing versus value‐reducing managers. We use a large sample of bank mergers to test these predictions and find that the value response to different explanatory variables is asymmetric. Our findings provide new insights into how the market values merger bids.     

Best foot forward or best for last in a sequential auction?

Should a seller with private information sell the best or worst goods first? Considering the sequential auction of two stochastically equivalent goods, we find that the seller has an incentive to impress buyers by selling the better good first because the seller's sequencing strategy endogenously generates correlation in the values of the goods across periods. When this impression effect is strong enough, selling the better good first is the unique pure‐strategy equilibrium. By credibly revealing to all buyers the seller's ranking of the goods, an equilibrium strategy of sequencing the goods reduces buyer information rents and increases expected revenues in accordance with the linkage principle.     

Foreign Aid and Consumption Smoothing: Evidence from Global Food Aid

The paper examines the cyclical properties of food aid with respect to food availability in recipient countries, with a view to assessing its impact on consumption in some 150 developing countries and transition economies, covering 1970 to 2000. The results show that global food aid has been allocated to countries most in need. Food aid has also been countercyclical within countries with the greatest need. However, for most countries, food aid is not countercyclical. The amount of food aid provided is also insufficient to mitigate contemporaneous shortfalls in consumption.     

Rezensionen

Ohne Zusammenfassung     

PRICING IN PUBLIC ENTERPRISES

The pricing in private and public enterprise differs primarily on the supply side. In the long run, private enterprises must cover total costs and provide an adequate return necessary to attract venture capital. In contrast, extra-commercial considerations may influence pricing in public enterprises. They may incur losses in the public interest under explicit directives from the government. A number of theories of pricing in public enterprises have been put forward. Most important of these are: (1) marginal cost of production theory; (2) no profit, no loss theory; (3) average cost of production theory; (4) theory of making profits. All these theories suffer from a number of weaknesses and none of them taken individually is a satisfactory guide for determining the prices of the products of public enterprises. There however exists a strong case for public enterprises, particularly in developing countries, to earn reasonable profits in pricing their products. Public enterprises fostered on public revenues must yield surpluses which can be used either for their own expansion or for financing the general development plans of the country. The profits which a public enterprise can earn are an important indication of the justification for the use of economic resources in that economic activity. Upholding the test of profit not only lessens possibilities of the investment decisions being subjected to political pressures but also safeguards against inefficiency in management. A policy of profits is essential for attaining the goal of building a socialist society. The amount of profits expected from different enterprises, however, cannot be uniform because of diverse objectives sought in the setting up of public enterprises, degree of essentiality of their products, nature of the services provided by them, size of their market, class of their consumers and their paying capacity, conditions of market under which they operate, their role in stimulating growth and social benefits conferred by them.