We investigate the methodology used in a significant genre of experimental economics, in which experiments are designed to test theoretical models by implementing them in the laboratory. Using two case studies, we argue that such an experiment is a test, not of what the model says about its target domain, but of generic theoretical components used in the model. The properties that make a model interesting as a putative explanation of phenomena in its target domain are not necessarily appropriate (...) for such tests. We consider how this research strategy has been legitimised within the community of experimental economists. (shrink)
The paper explores how, in economics and biology, theoretical models are used as explanatory devices. It focuses on a modelling strategy by which, instead of starting with an unexplained regularity in the world, the modeller begins by creating a credible model world. The model world exhibits a regularity, induced by a mechanism in that world. The modeller concludes that there may be a part of the real world in which a similar regularity occurs and that, were that the case, the (...) model would offer an explanation. Little concrete guidance is given about where such a regularity might be found. Three modelling exercises in evolutionary game theory—one from economics and two from biology—are used as case studies. Two of these (one from each discipline) exemplify ‘explanation in search of observation’. The third goes a step further, analysing a regularity in a model world and treating it as informative about the real world, but without saying anything about real phenomena. The paper argues that if the relation between the model and real worlds is understood in terms of similarity, and if modelling is understood as an ongoing discovery process rather than as the demonstration of empirical truths, there can be value in creating explanations before finding the regularities that are to be explained. (shrink)
This paper asks how, in science in general and in economics in particular, theoretical models aid the understanding of real-world phenomena. Using specific models in economics and biology as test cases, it considers three alternative answers: that models are tools for isolating the ‘capacities’ of causal factors in the real world; that modelling is ‘conceptual exploration’ which ultimately contributes to the development of genuinely explanatory theories; and that models are credible counterfactual worlds from which inductive inferences can be made. The (...) paper argues that the ‘credible worlds’ account captures significant aspects of scientific practice, even if many modellers see their work as conceptual exploration. (shrink)
This paper defines and analyses the concept of a 'ranking problem'. In a ranking problem, a set of objects, each of which possesses some common property P to some degree, are ranked by P-ness. I argue that every eligible answer to a ranking problem can be expressed as a complete and transitive 'is at least as P as' relation. Vagueness is expressed as a multiplicity of eligible rankings. Incommensurability, properly understood, is the absence of a common property P. Trying to (...) analyse incommensurability in the same framework as ranking problems causes unnecessary confusion. (shrink)
Until recently, economics was generally understood to be a nonexperimental science with a hypothetico‐deductive methodology. This article considers how the methodology of economics has changed with the spread of experimental methods. Initially, most experimental economists saw their work as testing pre‐existing theories. However, a method of systematic inductive enquiry in which theory plays a less central role is now evolving. This method is structured around the discovery and progressive refinement of regularities. “Exhibits”—experimental designs that generate significant regularities—are taking over some (...) of the functions formerly performed by theoretical models. †To contact the author, please write to: School of Economics, University of East Anglia, Norwich NR4 7TJ, UK; e‐mail: r.sugden@uea.ac.uk. (shrink)
To appear in "Rationality and Commitment" Feb 2008 http://www.oup.com/us/catalog/general/subject/Philosophy/EthicsMoralPhilosophy/?view=usa&ci=97801992 87260.
I compare Mill's and Sen's accounts of the value of opportunity, focusing on a tension between two ideas they both uphold: that individual freedom is an important component of well-being, and that, because desires can be adaptive, actual desire is not always a good indicator of what will give well-being. The two writers' responses to this tension reflect different understandings of the relationship between freedom and desire. Sen links an individual's well-being to her freedom to choose what she has reason (...) to desire, and looks to a democratic political process for a collective judgement about what it is rational to desire. Mill links the individual's well-being to her freedom to act on her own desires, whatever they may be, within the constraints imposed by a fair initial distribution of resources. He sees no need for collective judgement about what is ultimately valuable in human life. I side with Mill. (Published Online February 16 2006). (shrink)
Two roles of experiments in behavioural economics are distinguished ? experiments as exhibits and experiments as tests of theories. An exhibit is an experimental design which reliably induces a surprising regularity, typically combined with an informal hypothesis about the underlying causal mechanism. ?Deviation theories? ? generalisations of received theories which incorporate additional causal mechanisms ? are constructed so as to be consistent with known exhibits, and tested in new situations. The paper argues that the principles of good practice are different (...) for the two types of experiment, in part because of a tendency for successful exhibits to be produced by several causal mechanisms. (shrink)
David Lewis is widely credited with the first formulation of common knowledge and the first rigorous analysis of convention. However, common knowledge and convention entered mainstream game theory only when they were formulated, later and independently, by other theorists. As a result, some of the most distinctive and valuable features of Lewis' game theory have been overlooked. We re-examine this theory by reconstructing key parts in a more formal way, extending it, and showing how it differs from more recent game (...) theory. In contrast to current theories of common knowledge, Lewis' theory is based on an explicit analysis of the modes of reasoning that are accessible to rational individuals and so can be used to analyse the genesis of common knowledge. Lewis' analysis of convention emphasises the role of inductive reasoning and of salience in the maintenance of conventions over time. Footnotes Earlier versions of this paper were presented at the 13th Amsterdam Colloquium at the University of Amsterdam, at a workshop on social norms at Wissenschaftskolleg zu Berlin, and at seminars at Tilburg University and the University of Bristol. We are grateful for comments from participants at those meetings, from two anonymous referees, and from Michael Bacharach, Nick Bardsley, Cristina Bicchieri, Luc Bovens, Simon Grant, David McCarthy, Shepley Orr, Brian Skyrms, Peter Vanderschraaf, Peter Wakker and Jörgen Weibull. Robert Sugden's work was supported by the Leverhulme Trust. (shrink)
Abstract Orthodox decision theory presupposes that agency is invested in individuals. An opposing literature allows team agency to be invested in teams whose members use distinctive modes of team reasoning. This paper offers a new conceptual framework, inspired by David Lewis's analysis of common reasons for belief, within which team reasoning can be represented. It shows how individuals can independently endorse a principle of team reasoning which prescribes acting as a team member conditional on assurance that others have endorsed the (...) same principle. It argues that there can be such assurance even when no individual has an obligation to act on team reasoning. *This paper originated in a lecture that I gave at a Colloquium on Collective Intentions at Erasmus University Rotterdam. I thank participants, and particularly Govert den Hartogh, for comments. The analysis presented in this paper is an offshoot of a larger project, which uses David Lewis's work as the starting point for a reconstruction of the foundations of game theory. That project is joint work with Robin Cubitt. The specific idea of using this approach to analyse team reasoning grew out of a discussion with Michael Bratman. My work was supported by the Leverhulme Trust. (shrink)
The discovered preference hypothesis appears to insulate expected utility theory (EU) from disconfirming experimental evidence. It asserts that individuals have coherent underlying preferences, which experiments may not reveal unless subjects have adequate opportunities and incentives to discover which actions best satisfy their preferences. We identify the confounding effects to be expected in experiments, were that hypothesis true, and consider how they might be controlled for. We argue for a design in which each subject faces just one distinct choice task for (...) real. We review the results of some tests of EU which have used this design. These tests reveal the same violations of the independence axiom as other studies have found. We conclude that the discovered preference hypothesis does not justify scepticism about the reality of these effects. (shrink)
An experiment is reported which tests for positive confirmation bias in a setting in which individuals choose what information to buy, prior to making a decision. The design â an adaptation of Wason's selection task â reveals the use that subjects make of information after buying it. Strong evidence of positive confirmation bias, in both information acquisition and information use, is found; and this bias is found to be robust to experience. It is suggested that the bias results from a (...) pattern of reasoning which, although producing sub-optimal decisions, is internally coherent and which is self-reinforcing. (shrink)
It is a truism that a market economy cannot function without trust. We must be able to rely on other people to respect our property rights, and on our trading partners to keep their promises. The theory of economics is incomplete unless it can explain why economic agents often trust one another, and why that trust is often repaid. There is a long history of work in economics and philosophy which tries to explain the kinds of reasoning that people use (...) when they engage in practices of trust: this work develops theories of trust. A related tradition in economics, sociology and political science investigates the kinds of social institution that reproduce whatever habits, dispositions or modes of reasoning are involved in acts of trust: this work develops theories of social capital. A recurring question in these literatures is whether a society which organizes its economic life through markets is capable of reproducing the trust on which those markets depend. In this paper, we look at these themes in relation to the writings of three eighteenth-century philosopher-economists: David Hume, Adam Smith, and Antonio Genovesi. (shrink)
Using as examples Akerlof's 'market for ''lemons''' and Schelling's 'checkerboard' model of racial segregation, this paper asks how economists' abstract theoretical models can explain features of the real world. It argues that such models are not abstractions from, or simplifications of, the real world. They describe counterfactual worlds which the modeller has constructed. The gap between model world and real world can be filled only by inductive inference, and we can have more confidence in such inferences, the more credible the (...) model is as an account of what could have been true. (shrink)
When my family discusses how we should spend a summer holiday, we start from certain common understandings about our preferences. We prefer self-catering accommodation to hotels, and hotels to campsites. We prefer walking and looking at scenery and wildlife to big-city sightseeing and shopping. When it comes to walks, we prefer walks of six miles or so to ones which are much shorter or much longer, and prefer well-marked but uncrowded paths to ones which are either more rugged or more (...) popular. And so on. These common understandings greatly simplify the task of choosing between holiday destinations and activities, by allowing us quickly to eliminate many options. But what does it mean to say that we prefer one thing to another? (shrink)
