Intertemporal Choice of Fuzzy Soft Sets

This paper first merges two noteworthy aspects of choice. On the one hand, soft sets and fuzzy soft sets are popular models that have been largely applied to decision making problems, such as real estate valuation, medical diagnosis (glaucoma, prostate cancer, etc.), data mining, or international trade. They provide crisp or fuzzy parameterized descriptions of the universe of alternatives. On the other hand, in many decisions, costs and benefits occur at different points in time. This brings about intertemporal choices, which may involve an indefinitely large number of periods. However, the literature does not provide a model, let alone a solution, to the intertemporal problem when the alternatives are described by (fuzzy) parameterizations. In this paper, we propose a novel soft set inspired model that applies to the intertemporal framework, hence it fills an important gap in the development of fuzzy soft set theory. An algorithm allows the selection of the optimal option in intertemporal choice problems with an infinite time horizon. We illustrate its application with a numerical example involving alternative portfolios of projects that a public administration may undertake. This allows us to establish a pioneering intertemporal model of choice in the framework of extended fuzzy set theorie

Weighted logics for artificial intelligence : an introductory discussion

International audienceBefore presenting the contents of the special issue, we propose a structured introductory overview of a landscape of the weighted logics (in a general sense) that can be found in the Artificial Intelligence literature, highlighting their fundamental differences and their application areas

An overview of decision table literature 1982-1995.

This report gives an overview of the literature on decision tables over the past 15 years. As much as possible, for each reference, an author supplied abstract, a number of keywords and a classification are provided. In some cases own comments are added. The purpose of these comments is to show where, how and why decision tables are used. The literature is classified according to application area, theoretical versus practical character, year of publication, country or origin (not necessarily country of publication) and the language of the document. After a description of the scope of the interview, classification results and the classification by topic are presented. The main body of the paper is the ordered list of publications with abstract, classification and comments.

Happiness, Morality, and Game Theory

Non-cooperative Games, Happiness, Morality.

The efficiency of the non-profit enterprise: constitutional ideology, conformist preferences and reputation

According to one thesis the non profit enterprise (in short NPE) is able to attract ideological entrepreneurs and workers (Rose-Ackerman 1996). In fact I prove that without the ideological element, a simple game between the entrepreneur, worker and beneficiary is condemned to an opportunistic equilibrium, beneficial to the internal members of the organization but detrimental to the beneficiary. Thus the NPE does not better than its for profit counterpart. In my model ideologues, both entrepreneurs and workers, share a principle of justice seen as the constitutional ideology of the NPE, agreed upon in an hypothetical ex ante bargaining game. The constitutional principle provides an independent source of motivation (a source of utility) of the players, in so far as they believe in the reciprocity of conformity to the ideology by all the participants. I call this conformity-based utility “ideological”, and I see it as the representation of a preference for expected conformity to the given constitutional principle. The philosophical underpinnings of this reform of the players' utility functions in worked out by distinguishing two concepts of preferences of the Self: consequentialist preferences and conformist preferences. The latter are preferences for those actions that are part of states of affairs described in terms of interdependent actions conforming to an abstract norm or principle, which become effective once the preferences' holder does expect that the other players do they part in that state of affairs and they do expect that himself do his part in the same state of affairs. What result is that a player's ideological utility depends on the expectation of deontological modes of behaviour followed by all the participants, himself included. On this basis it is possible to overcome personal incentives to embrace opportunistic behaviour, so that the proper Non-profit Enterprise emerges. It is proved that in the “social enterprise game” amongst the member of the organisation there exists an organisational equilibrium minimising transaction costs to the beneficiaries. At last, this equilibrium rests on the emergence of an expectations system of reciprocal conformity to the constitutional ideology. As the existence - not even the selection – of the internal organizational equilibrium rests heavily on the existence of the appropriate system of reciprocal expectation, the problem of how we can justify the emergence of the appropriate system of beliefs must be underlined. Here is where the explicit moral codes of the NPE enters the scene. I see the code of ethics as the building block for deriving a reputation equilibrium between the NPE as a whole and its external stakeholders within a repeated game, whose stage-game is the typical game of trust played under incomplete knowledge and unforeseen contingencies. At last the conformist-motivation model and the reputation model under unforeseen contingencies are shown to play together in a mutually supporting explanation of the efficiency of the NPE.

Paradoxes versus formalism in economics. Evidence from the early years of game theory and experimental economics

This paper argues that the acceptance of two recent methodological advances in economics, namely game theory and laboratory experimentation, was affected by the history dependence constraining the formalization of economics. After an early period in which the two methods were coolly received by economists because their applications challenged some basic hypotheses of mainstream economics, their subsequent acceptance was the result of the corroboration of those same hypotheses. However, the recent emergence of some paradoxes has finally revealed that the effectiveness of game theory and experimental techniques in economics is improved when descriptively implausible and normatively unsatisfactory assumptions such as the centrality of individual maximization in decision theory and the definition of rationality as consistency in preferences are revised.paradoxes, game theory, experiments, individual maximization, economic rationality