Six hens pecked a key (Experiment 1) or pushed a door (Experiment 2) to obtain food reinforcement. In both experiments and as an analogue of price changes, the response requirements were varied in two ways: by increasing the number of responses required and by increasing the required force of each response. The two price manipulations (response number and response force) had different effects o...

‎Unmixed bipartite graphs have been characterized by Ravindra and‎ ‎Villarreal independently‎. ‎Our aim in this paper is to‎ ‎characterize unmixed $r$-partite graphs under a certain condition‎, ‎which is a generalization of Villarreal's theorem on bipartite‎ ‎graphs‎. ‎Also, we give some examples and counterexamples in relevance to this subject‎.

This paper examines the competitiveness of winner-take-all price competition in homogeneous product oligopoly environments where underlying buyer demands and/or firms’ costs need not be continuous. Our analysis is motivated by the observation that a variety of economic settings have these features. For example, in 1996 an Ivy League university solicited bids from several vendors for its initiat...

According to static models of industrial organization, a rise in competition decreases prices. In this paper, I test whether this conclusion can be reversed in the mobile telecommunications markets where dynamic e ciency e ects might be signi cant. The empirical test relies on the change in the intensity of competition introduced by the entry of the fourth mobile operator in France and the merg...

A recent strategy carried out by the aircraft industry to reduce the total cost of the new generation fighters has consisted in the development of a single airframe with different technical and operational specifications. This strategy has been designed to reduce costs in the Research, Design and Development phase with the ultimate objective of reducing the final unit price per aircraft. This i...

In estimating the cost-effectiveness of diagnostic procedures, it is helpful to treat diagnostic information as a commodity with a unit price. The amount of useful information provided by a test result can be measured in binary units (bits), and the unit price of the information produced by the test result can be expressed in dollars per bit in much the same way that the price of gold is given ...