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Working Papers | 2000

The Top Cycle And Uncovered Solutions for Abstract Games: Axiomatic Characterizations

Lahiri Somdeb

In this paper we consider binary relations which are reflexive and complete. Such binary relations are referred to in the literature as abstract games. Given an abstract game a (game)solution is a function which associates to each subset a non-empty collection of points of the subset. In this paper we provide axiomatic characterizations of the top cycle and uncovered solutions for abstract games. In a final section of the paper, the similarity between a game solution and a choice function of classical rational choice theory is exploited to axiomatically characterize the top cycle and uncovered choice functions.

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Working Papers | 2000

A Study of Learned Helplessness & Perceived Role Efficacy Among Executives in Pharmaceutical Industry

Pestonjee D M, Oza Shweta, and Sayeed-uz-Zafar

Learned Helplessness is a cognitive state of being which believes that whatever it does is not going to alter the outcome of an event. In the other words, it comes to believe in response-outcome-non-contingency. Role efficacy can be seen as the psychological factor underlying role effectiveness, in short role efficacy is the potential effectiveness of a role. A total of 40 executives of pharmaceutical industry were used as sample. After using appropriate statistical tools it was found that moderate level of learned helplessness were prevailing among them and dominant LH factors include LH1, LH4 and LH6. While on role efficacy moderate effectiveness were observed Centrality, Proactivity, Superordination and Influence needs special attention to improve the effectiveness of the executives. Some significant correlation were also observed among various factors of Learned Helplessness and Perceived Role Efficacy.

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Working Papers | 2000

Coastal Shipping: Scope of Integrating with the National Transport Network

G. Raghuram

Coastal shipping constitutes about 30% of the total traffic handled at our ports. Exhibit 1 gives data for the past two years for the major ports, the Gujarat Maritime Board (GMB) ports, and the non-GMB minor and intermediate ports. We see that the total coastal traffic for 1998-99 was 87.4 million tonnes (mt.). Out of this, 75.8 mt (86.7%) was handled in the major ports, 6.4 mt (7.3%) was handled in the GMB ports and the rest 5.2 mt (5.9%) in the non-GMB minor and intermediate ports.

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Working Papers | 2000

Axiomatic Characterisation of Weighted Voting Operator

Lahiri Somdeb

A federation voting operator allows a finite set of coalitions to unilaterally elect any outcome. There are several special types of federation voting operators, all of which share a property: the candidates are assigned weights, and for a coalition to be decisive, it is necessary that the sum of the weights of its members exceed a pre-assigned quota. In this paper we address the following question: When is a Federation Voting Operator a Weighted Voting Operator?

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Working Papers | 2000

Threshold of Median Rank Solutions

Lahiri Somdeb

In this paper we consider solutions defined on the class of transitive tournaments. Such solutions are essentially rank solutions i.e. solutions which depend on the ranks of the alternatives and not on any other physical characteristic. A solution is said to be a threshold solution, if for every feasible set of alternatives there exists an alternative such that the solution set coincides with the set of feasible alternatives which are not worse than the assigned alternative. We provide an axiomatic characterization of such solutions using two properties. The first property is functional acyclicity. The second property requires that given any set containing just two alternatives only the alternative only the alternative with the higher rank is selected. In order to make the presentation self contained we also provide a simple proof of an extension theorem, which is used to prove two the above mentioned axiomatic characterization. Subsequently, we provide two theorems which characterizes the median choice function when the universal set has atleast three alternatives. Several examples are provided to highlight the relationship between the axioms emphasised in this paper. It is also noted here that our second axiomatic characterization breaks down if the universal set contains precisely two elements. Following our discussion of the median rank solution, we provide two more axiomatic characterization. The first is a simultaneous axiomatic characterization of two solutions: one being that which always chooses the element with the highest rank form a set and the other being that which always selects the element with the lowest rank from a set. The second is also a simultaneous axiomatic characterization of two solutions: one being that which always chooses the greatest element from the median choice set of a set and the other being that which always selects the least element from the median choice set of a set.

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Working Papers | 2000

Abstract Games Admitting Stable Solutions

Lahiri Somdeb

Reflexive and complete binary relations are also referred to as abstract games. An ordered pair comprising a non-empty subset of the universal set and an abstract game is referred to as a subgame. A (game) solution is a function which associates to all subgames of a given (nonempty) set of games, a nonempty subset of the set in the subgame. In this paper we obtain conditions which are either necessary or sufficient for an abstract game to admit a solution which always selects a von Neumann-Morgenstern stable set from every admissible subgame. It is proved in this paper that a sufficient condition for an abstract game to satisfy this property is that it does not admit any strict preference cycle of length three and satisfy what we call stable five element set property. We show by an example that these two properties are logically independent.

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Working Papers | 2000

Local Social Decision Functions: A Survey

Lahiri Somdeb

Since the publication of Arrow's (1951) impossibility theorem, much effort has been spent on the analysis and rationalizability of committee decision making. The traditional approach to this problem considers rules which aggregate individual binary relations to a binary relation for society. In this survey we call such rules, which are assumed to be defined on profiles of individual rankings, by the name social decision functions. In Aleskerov (1999) can be found a property that social decision functions are required to satisfy. This property is called locality. In Arrow's original work it was called independence of irrelevant alternatives. Social Decision functions which satisfy locality are called local social decision functions. Aleskerov (1999) not only contains a state of the art survey of local social decision functions, but several original contributions to the literature as well. However, Aleskerov does not restrict the domain of social decision functions to be profiles of individual rankings. In different characterization of individual rankings as a subset and usually as a strict subset. It is well known in the theory of axiomatic choice theory that a characterization valid on a given domain may fail to hold on a subdomain. Our purpose in this survey is to show that such is not the case with local social decision functions. It is necessary to justify the domain we have chosen for our survey. Social sciences in general and economic theory in particular, has never confronted any major problem while representing individual preferences by a strict ranking. It is only the issue concerning social preferences by a strict ranking which has been at the centre of the debate concerning aggregation of preferences in social choice theory. Thus the domain comprising profiles of individual rankings is consistent with the demands of economic theory and yet highlights the problems that arise very naturally in social aggregation procedures.

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Working Papers | 2000

Privatisation: Issues and Evidence

T. T. Ram Mohan

Even as India's privatisation programme gathers steam, there is a perception, reflected in the pronouncements of ministers as well as in writings in the popular press, that the benefits of privatisation can be taken as axiomatic. There is little in the literature on privatisation that lends support to such dogma. The theoretical literature, while pointing to the benefits or private ownership, also underlines the conditions under which such benefits an be realised. These conditions cannot be presumed to operate everywhere. The empirical evidence is also shrouded in ambiguities, whether we look at the experience in the developed world or in developing countries. This paper surveys the literature on privatisation and highlights the conceptual issues underlying privatisation as well as the evidence from privatisation experiments in different parts of the world.

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Working Papers | 2000

eTime

Singh J P

The paper examines various measures of time and argues that none of the measures meet the needs of commerce and law for transactions carried out in the cyberspace. It therefore suggests that a new measure of the time and epoch, called eTime be introduced. The paper further suggests that the assumed zero of eTime should be the epoch of signing 'A Declaration of Independence of Cyberspace', i.e. Fri, Feb 9, 1996 17:16:35 +0100 at Davos, Switzerland.

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Working Papers | 2000

The Lexicographic Composition of Abstract Games

Lahiri Somdeb

Two stage selection procedures are quite common. Decisions arrived at on the basis of the composition of the binary relations in some form, is what is implemented in such two stage choice procedures. The resulting binary relation is referred to as a lexicographic composition of the individual binary relations. In this paper we begin by obtaining a necessary and sufficient condition for a quasi transitive binary relation to be transitive. Then we obtain necessary and sufficient conditions for the lexicographic composition of two quasi transitive binary relations to be quasi transitive. In passing it is noted that the lexicographic composition of two transitive binary relations is always transitive. Finally, we obtain conditions for the lexicographic composition of two binary relations to be acyclic. It is observed that if the second stage binary relation is acyclic, then the lexicographic composition is acyclic if and only if the first stage binary relation is. All our binary relations are assumed to be reflexive and complete. Such binary relations are called abstract games.

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