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The Selfish Gene

Richard Dawkins — 2005-06-07T20:44:00-00:00

(01 September 1990)

Inheriting the mantle of revolutionary biologist from Darwin, Watson, and Crick, Richard Dawkins forced an enormous change in the way we see ourselves and the world with the publication of The Selfish Gene. Suppose, instead of thinking about organisms using genes to reproduce themselves, as we had since Mendel's work was rediscovered, we turn it around and imagine that "our" genes build and maintain us in order to make more genes. That simple reversal seems to answer many puzzlers which had stumped scientists for years, and we haven't thought of evolution in the same way since. Why are there miles and miles of "unused" DNA within each of our bodies? Why should a bee give up its own chance to reproduce to help raise her sisters and brothers? With a prophet's clarity, Dawkins told us the answers from the perspective of molecules competing for limited space and resources to produce more of their own kind. Drawing fascinating examples from every field of biology, he paved the way for a serious re-evaluation of evolution. He also introduced the concept of self-reproducing ideas, or memes, which (seemingly) use humans exclusively for their propagation. If we are puppets, he says, at least we can try to understand our strings. --Rob Lightner Richard Dawkins' brilliant reformulation of the theory of natural selection has the rare distinction of having provoked as much excitement and interest outside the scientific community as within it. His theories have helped change the whole nature of the study of social biology, and have forced thousands of readers to rethink their beliefs about life. In his internationally bestselling, now classic volume, The Selfish Gene, Dawkins explains how the selfish gene can also be a subtle gene. The world of the selfish gene revolves around savage competition, ruthless exploitation, and deceit, and yet, Dawkins argues, acts of apparent altruism do exist in nature. Bees, for example, will commit suicide when they sting to protect the hive, and birds will risk their lives to warn the flock of an approaching hawk. This revised edition of Dawkins' fascinating book contains two new chapters. One, entitled "Nice Guys Finish First," demonstrates how cooperation can evolve even in a basically selfish world. The other new chapter, entitled "The Long Reach of the Gene," which reflects the arguments presented in Dawkins' The Extended Phenotype, clarifies the startling view that genes may reach outside the bodies in which they dwell and manipulate other individuals and even the world at large. Containing a wealth of remarkable new insights into the biological world, the second edition once again drives home the fact that truth is stranger than fiction.

Broad exploration or precise specificity: Two basic information seeking patterns among students

Jannica Heinström — 2006-08-21T14:38:57-00:00

Journal of the American Society for Information Science and Technology, Vol. 57, No. 11. (2006), pp. 1440-1450.

This article investigates whether information seeking patterns can be related to discipline differences, study approaches, and personality traits. A quantitative study of 305 master's thesis students' information behavior found that their information seeking tended to be either exploratory or precise. Statistical analyses showed that inner traits seemed more influential than discipline characteristics on information behavior. Exploration or specificity was manifested in terms of both the level and scope of information students wished to retrieve and the way they searched for it.

The Internet Galaxy: Reflections on the Internet, Business, and Society

Manuel Castells — 2005-04-26T22:51:11-00:00

(01 December 2001)

The Power of Identity (The Information Age)

Manuel Castells — 2005-02-28T15:53:09-00:00

(01 November 2003)

The Power of Identity is the second volume of Manuel Castells’s trilogy, The Information Age: Economy, Society, and Culture. It deals with the social, political, and cultural dynamics associated with the technological transformation of our societies and with the globalization of the economy. It analyzes the importance of cultural, religious, and national identities as sources of meaning for people, and the implications of these identities for social movements. It studies grassroots mobilizations against the unfettered globalization of wealth and power, and considers the formation of alternative projects of social organization, as represented by the environmental movement and the women’s movement. It also analyzes the crisis of the nation-state and its transformation into a network state, and the effects on political democracies of the difficulties of international governance and the submission of political representation to the dictates of media politics and the! politics of scandal. This substantially expanded second edition updates and elaborates the analysis of these themes, adding new sections on al-Qaeda and global terrorist networks, on the anti-globalization movement, on American unilateralism and the conflicts of global governance, on the crisis of political legitimacy throughout the world, and on the theory of the network state.

The Rise of the Network Society (Castells, Manuel. Information Age, 1.)

Manuel Castells — 2005-05-15T18:25:06-00:00

(01 September 1996)

The Rise of the Network Society, the first volume in a trilogy collectively known as the Information Age, has earned Manuel Castells comparisons to such illustrious social critics as Max Weber and Karl Marx. Just as they worked to make sense of industrial capitalism, so does Castells put forth a systemic analysis of the global informational capitalism that emerged in the last half of the 20th century. While many books have considered the development of increasingly sophisticated information technology, the shifting conditions of employment and responsibility within corporations, or the rise of corporations whose domains are spread out over several nation-states, Castells unites these topics in a comprehensive thesis, negotiating the tightrope between academic sociology and mainstream business analysis.

Theories of the Information Society (The International Library of Sociology)

Frank Webster — 2005-05-05T22:32:35-00:00

(01 May 2002)

Archeology of Knowledge

Michel Foucault — 2005-05-11T21:12:47-00:00

(12 September 1982)

The Social Life of Information

John Brown — 2005-04-05T01:40:53-00:00

(10 March 2000)

How many times has your PC crashed today? While Gordon Moore's now famous law projecting the doubling of computer power every 18 months has more than borne itself out, it's too bad that a similar trajectory projecting the reliability and usefulness of all that power didn't come to pass, as well. Advances in information technology are most often measured in the cool numbers of megahertz, throughput, and bandwidth--but, for many us, the experience of these advances may be better measured in hours of frustration. The gap between the hype of the Information Age and its reality is often wide and deep, and it's into this gap that John Seely Brown and Paul Duguid plunge. Not that these guys are Luddites--far from it. Brown, the chief scientist at Xerox and the director of its Palo Alto Research Center (PARC), and Duguid, a historian and social theorist who also works with PARC, measure how information technology interacts and meshes with the social fabric. They write, "Technology design often takes aim at the surface of life. There it undoubtedly scores lots of worthwhile hits. But such successes can make designers blind to the difficulty of more serious challenges--primarily the resourcefulness that helps embed certain ways of doing things deep in our lives." The authors cast their gaze on the many trends and ideas proffered by infoenthusiasts over the years, such as software agents, "still a long way from the predicted insertion into the woof and warp of ordinary life"; the electronic cottage that Alvin Toffler wrote about 20 years ago and has yet to be fully realized; and the rise of knowledge management and the challenges it faces trying to manage how people actually work and learn in the workplace. Their aim is not to pass judgment but to help remedy the tunnel vision that prevents technologists from seeing larger the social context that their ideas must ultimately inhabit. The Social Life of Information is a thoughtful and challenging read that belongs on the bookshelf of anyone trying to invent or make sense of the new world of information. --Harry C. Edwards To see the future we can build with information technology, we must look beyond mere information to the social context that creates and gives meaning to it.For years pundits have predicted that information technology will obliterate the need for almost everything-from travel to supermarkets to business organizations to social life itself. Individual users, however, tend to be more skeptical. Beaten down by info-glut and exasperated by computer systems fraught with software crashes, viruses, and unintelligible error messages, they find it hard to get a fix on the true potential of the digital revolution.John Seely Brown and Paul Duguid help us to see through frenzied visions of the future to the real forces for change in society. They argue that the gap between digerati hype and end-user gloom is largely due to the "tunnel vision" that information-driven technologies breed. We've become so focused on where we think we ought to be-a place where technology empowers individuals and obliterates social organizations-that we often fail to see where we're really going and what's helping us get there. We need, they argue, to look beyond our obsession with information and individuals to include the critical social networks of which these are always a part.Drawing from rich learning experiences at Xerox PARC, from examples such as IBM, Chiat/Day Advertising, and California's "Virtual University," and from historical, social, and cultural research, the authors sharply challenge the futurists' sweeping predictions. They explain how many of the tools, jobs, and organizations seemingly targeted for future extinction in fact provide useful social resources that people will fight to keep. Rather than aiming technological bullets at these "relics," we should instead look for ways that the new world of bits can learn from and complement them. Arguing elegantly for the important role that human sociability plays, even-perhaps especially-in the world of bits, The Social Life of Information gives us an optimistic look beyond the simplicities of information and individuals. It shows how a better understanding of the contribution that communities, organizations, and institutions make to learning, working and innovating can lead to the richest possible use of technology in our work and everyday lives. Drawing from recent research and practical examples across a range of organizations, The Social Life of Information dispels many of the futurists' sweeping predictions that information technology will obliterate the need for everything from travel to supermarkets to business organizations to social life itself. The authors examine the potential and limitations of technology with regard to intelligent software agents, the automated home office, business reorganization for innovation, knowledge management and work practices, the paperless society, and the digital university. Arguing eloquently for the important role human sociability plays in the world of bits, Brown and Duguid give us an optimistic look beyond the simplicities of information and individuals. They show how a better understanding of the contribution that communities, organizations, and institutions make to learning, knowledge, and judgment can lead to the richest possible use of technology in our work and everyday lives.

The Social Construction of Reality : A Treatise in the Sociology of Knowledge

Peter Berger — 2005-05-11T21:02:37-00:00

(11 July 1967)

Ecologies of Knowledge: Work and Politics in Science and Technology

Susan Star — 2005-05-11T20:35:40-00:00

(01 August 1995)

Agents that reduce work and information overload

Pattie Maes — 2005-07-11T16:37:12-00:00

Commun. ACM, Vol. 37, No. 7. (July 1994), pp. 30-40.

An Ontological Model of an Information System

Yair Wand — 2005-10-28T10:47:06-00:00

IEEE Trans. Softw. Eng., Vol. 16, No. 11. (November 1990), pp. 1282-1292.

Research Commentary: An Agenda for Information Technology Research in Heterogeneous and Distributed Environments

Salvatore March — 2005-10-28T10:28:21-00:00

Information Systems Research, Vol. 11, No. 4. (December 2000), pp. 327-341.

The information technology interaction model: a foundation for the MBA core course

Mark Silver — 2005-10-28T10:14:21-00:00

MIS Quarterly, Vol. 19, No. 3. (September 1995), pp. 361-390.

Conceptual Modeling Quality - From EER to UML Schemas Evaluation

Samira Cherfi — 2005-07-26T14:22:55-00:00

Lecture Notes in Computer Science, Vol. 2503 (January 2002), pp. 414-428.

This exploratory research investigates the evaluation process of conceptual specifications developed using either Extended Entity-Relationship (EER) or Unified Modeling Language (UML) conceptual models. In this paper, we provide a comprehensive framework for evaluating EER and UML conceptual schemas. Furthermore, we define classes of metrics facilitating the evaluation process and leading to the choice of the appropriate representation among several schemas describing the same reality. Based on quality criteria proposed in the literature, we select a subset of criteria relevant to conceptual EER schema quality evaluation. For each criterion we define one or several metrics allowing the designer to measure the schema quality. We evaluate alternative EER conceptual schemas representing the same universe of discourse using the appropriate criteria and their associated metrics. Finally, we extrapolate this evaluation process to UML schemas. Following the development of our framework, we analyze a case study and provide evidence in the support of the usefulness of the framework. Keywords: Conceptual modeling quality, quality criteria, quality metrics, user validation

Experimenting with Linguistic Tools for Conceptual Modelling: Quality of the Models and Critical Features

Nadzeya Kiyavitskaya — 2005-07-26T14:11:48-00:00

Lecture Notes in Computer Science, Vol. 3136 (January 2004), pp. 135-146.

Improving the Quality of Entity Relationship Models - Experience in Research and Practice

Daniel Moody — 2005-07-26T14:06:19-00:00

Lecture Notes in Computer Science, Vol. 1507 (January 1998), pp. 255-276.

This paper is an extension of previous research which developed a framework for evaluating and improving the quality of Entity Relationship models. The framework has now been used extensively in research and practice, including application in two of the largest commercial organisations in Australia. The experiences gained have been used to further develop and refine the framework. This paper describes how the framework has been used to: (a) quality assure data models as part of application development projects (product quality); (b) reengineer application development procedures to build quality into the data modelling process (process quality); (c) provide automated support for the evaluation process (Data Model Quality Advisor); (d) investigate the differences between data models produced by expert and novice data modellers. The results show that use of the framework has the potential to significantly improve research, practice and teaching of data modelling.

The Guidelines of Modeling - An Approach to Enhance the Quality in Information Models

Reinhard Schuette — 2005-07-26T14:03:19-00:00

Lecture Notes in Computer Science, Vol. 1507 (January 1998), pp. 240-254.

Although the necessity of building models seems obvious, it is astonishing that only few works deal with the fundamental problems of modeling - how models need to be understood from an epistemological point of view (e.g.: how does a modeler come to a model; why and in which ways do models built by different designers differ from another). The paper bases on the assumption that the subjective position of the modeler is the characterizing issue for the result of the modeling process - and that this subjectivity needs to be managed. We derive from this assumption the need for a sound structural framework in order to deal with the subjectivism of building models. With the Guidelines of Modeling (GoM) we present a framework of principles that improve the quality of information models by reducing the subjectivism in the information modeling process. The quality of modeling is supported by recommendations for an efficient, comprehensive, and correct design of information models. In the first part of the paper the guidelines are derived from the specific problems that stem from the subjective process of the system design. The Guidelines of Modeling contain six principles to ameliorate the quality of information modeling which are described in detail. Subsequently, the basic guidelines are placed in a structural framework, the GoM-Architecture, which consists of two dimensions: 1 st the range of model-use (reference models for a class of organizations or an industry, and company-specific models) and 2 nd the degree of precision or concretion (general, system views, and description language).

Metrics for Evaluating the Quality of Entity Relationship Models

Daniel Moody — 2005-07-26T13:57:42-00:00

Lecture Notes in Computer Science, Vol. 1507 (January 1998), pp. 211-225.

This paper defines a comprehensive set of metrics for evaluating the quality of Entity Relationship models. This is an extension of previous research which developed a conceptual framework and identified stakeholders and quality factors for evaluating data models. However quality factors are not enough to ensure quality in practice, because different people will have different interpretations of the same concept. The objective of this paper is to refine these quality factors into quantitative measures to reduce subjectivity and bias in the evaluation process. A total of twenty five candidate metrics are proposed in this paper, each of which measures one of the quality factors previously defined. The metrics may be used to evaluate the quality of data models, choose between alternatives and identify areas for improvement.

Informationsmanagement

Helmut Krcmar — 2005-05-26T15:54:55-00:00

(31 December 2004)

Case-based, problem-based learning -- Information literacy for the real world

Linda Carder — 2004-12-01T18:27:17-00:00

Research Strategies, Vol. 18, No. 3. (2001), pp. 181-190.

Shannon information and biological fitness

CT Bergstrom — 2006-09-12T08:47:15-00:00

Information Theory Workshop, 2004. IEEE (2004), pp. 50-54.

When studying information, biologists and behavioral scientists often eschew Shannon entropy. Instead, they commonly use a decision-theoretic measure of the value of information, on the grounds that Shannon's measure draws no distinction between useful and useless information. Here we show that these two measures are intimately related in the context of biological evolution. We present a simple model of evolution in an uncertain environment, and calculate the increase in Darwinian fitness that is made possible by information about the environmental state. This fitness increase - the fitness value of information - is a composite of both the Shannon entropy and the decision-theoretic measure of information value. Furthermore, the Shannon entropy of the environment, which seemingly fails to take anything about Darwinian fitness into account, nonetheless imposes an upper bound on the fitness value of information.

Estimating mutual information.

A Kraskov — 2005-01-21T15:52:08-00:00

Phys Rev E Stat Nonlin Soft Matter Phys, Vol. 69, No. 6 Pt 2. (June 2004)

We present two classes of improved estimators for mutual information M(X,Y), from samples of random points distributed according to some joint probability density mu(x,y). In contrast to conventional estimators based on binnings, they are based on entropy estimates from k -nearest neighbor distances. This means that they are data efficient (with k=1 we resolve structures down to the smallest possible scales), adaptive (the resolution is higher where data are more numerous), and have minimal bias. Indeed, the bias of the underlying entropy estimates is mainly due to nonuniformity of the density at the smallest resolved scale, giving typically systematic errors which scale as functions of k/N for N points. Numerically, we find that both families become exact for independent distributions, i.e. the estimator M(X,Y) vanishes (up to statistical fluctuations) if mu(x,y)=mu(x)mu(y). This holds for all tested marginal distributions and for all dimensions of x and y. In addition, we give estimators for redundancies between more than two random variables. We compare our algorithms in detail with existing algorithms. Finally, we demonstrate the usefulness of our estimators for assessing the actual independence of components obtained from independent component analysis (ICA), for improving ICA, and for estimating the reliability of blind source separation.

Information and fitness

Samuel Taylor — 2008-01-12T16:07:37-00:00

(28 Dec 2007)

The growth rate of organisms depends both on external conditions and on internal states, such as the expression levels of various genes. We show that to achieve a criterion mean growth rate over an ensemble of conditions, the internal variables must carry a minimum number of bits of information about those conditions. Evolutionary competition thus can select for cellular mechanisms that are more efficient in an abstract, information theoretic sense. Estimates based on recent experiments suggest that the minimum information required for reasonable growth rates is close to the maximum information that can be conveyed through biologically realistic regulatory mechanisms. These ideas are applicable most directly to unicellular organisms, but there are analogies to problems in higher organisms, and we suggest new experiments for both cases.

Information measures, effective complexity, and total information

Murray Gell-Mann — 2007-12-17T18:36:29-00:00

Complexity, Vol. 2, No. 1. (1996), pp. 44-52.

This article defines the concept of an information measure and shows how common information measures such as entropy, Shannon information, and algorithmic information content can be combined to solve problems of characterization, inference, and learning for complex systems. Particularly useful quantities are the effective complexity, which is roughly the length of a compact description of the identified regularities of an entity, and total information, which is effective complexity plus an entropy term that measures the information required to describe the random aspects of the entity. Mathematical definitions are given for both quantities and some applications are discussed. In particular, it is pointed out that if one compares different sets of identified regularities of an entity, the ?best? set minimizes the total information, and then, subject to that constraint, minimizes the effective complexity; the resulting effective complexity is then in many respects independent of the observer. © 1996 John Wiley & Sons, Inc.

Information content of binding sites on nucleotide sequences.

TD Schneider — 2005-03-09T21:21:57-00:00

J Mol Biol, Vol. 188, No. 3. (5 April 1986), pp. 415-431.

Repressors, polymerases, ribosomes and other macromolecules bind to specific nucleic acid sequences. They can find a binding site only if the sequence has a recognizable pattern. We define a measure of the information (R sequence) in the sequence patterns at binding sites. It allows one to investigate how information is distributed across the sites and to compare one site to another. One can also calculate the amount of information (R frequency) that would be required to locate the sites, given that they occur with some frequency in the genome. Several Escherichia coli binding sites were analyzed using these two independent empirical measurements. The two amounts of information are similar for most of the sites we analyzed. In contrast, bacteriophage T7 RNA polymerase binding sites contain about twice as much information as is necessary for recognition by the T7 polymerase, suggesting that a second protein may bind at T7 promoters. The extra information can be accounted for by a strong symmetry element found at the T7 promoters. This element may be an operator. If this model is correct, these promoters and operators do not share much information. The comparisons between R sequence and R frequency suggest that the information at binding sites is just sufficient for the sites to be distinguished from the rest of the genome.

Specificity, free energy and information content in protein-DNA interactions

Gary Stormo — 2008-04-24T04:20:34-00:00

Trends in Biochemical Sciences, Vol. 23, No. 3. (1 March 1998), pp. 109-113.

Site-specific DNA-protein interactions can be studied using experimental and computational methods. Experimental approaches typically analyze a protein-DNA interaction by measuring the free energy of binding under a variety of conditions. Computational methods focus on alignments of known binding sites for a protein, and, from these alignments, make estimates of the binding energy. Understanding the relationship between these two perspectives, and finding ways to improve both, is a major challenge of modern molecular biology.

Phenotypic Diversity, Population Growth, and Information in Fluctuating Environments.

Edo Kussell — 2005-09-23T21:32:25-00:00

Science, Vol. 309, No. 5743. (25 August 2005), pp. 2075-2078.

Organisms in fluctuating environments must adapt their behavior to survive. In clonal populations, this may be achieved through sensing followed by response, or through generation of diversity by stochastic phenotype switching. We show that stochastic switching can be favored over sensing when the environment changes infrequently. The optimal switching rates then mimic the statistics of environmental changes. We derive a relation between the long-term growth rate of the organism and the information available about its fluctuating environment.

Political economy, information and incentives

Jean-Jacques Laffont — 2008-07-01T09:53:21-00:00

European Economic Review, Vol. 43, No. 4-6. (April 1999), pp. 649-669.

This paper shows how the instruments of incentive theory can be used to develop some views about the proper design of governments to avoid the capture of politicians and bureaucrats by interest groups. First, treating politicians as informed supervisors to whom economic policy is delegated we show the usefulness of the separation of powers to increase the transaction costs of collusion, the relevance of asymmetric control for avoiding reciprocal favors. The incompleteness of the constitutional contract leaves discretion to politicians who become residual decision makers. We study the trade-offs between greater efficiency obtained by allowing powerful instruments to politicians and less discretion by restricting on the contrary those instruments. Determinants of those trade-offs are the variability of the environment, the extent of asymmetric information about tastes and technologies and the size of majorities. Finally, we show the new theory of incentives for group behavior can be used to determine the transaction costs of collusion under asymmetric information and to which extent these costs relax the constraints imposed on government by collusive behavior.

Hiding information in electoral competition

Paul Heidhues — 2008-07-01T09:34:34-00:00

Games and Economic Behavior, Vol. 42, No. 1. (January 2003), pp. 48-74.

We model a two-candidate electoral competition in which there is uncertainty about a policy-relevant state of the world. The candidates receive private signals about the true state, which are imperfectly correlated. We study whether the candidates are able to credibly communicate their information to voters through their choice of policy platforms. Our results show that the fact that private information is dispersed between the candidates creates a strong incentive for them to bias their messages toward the electorate's prior. Information transmission becomes more difficult, the less correlated are the candidates' signals, the lower is the signals' quality, and the stronger is the electorate's prior. Indeed, for weak priors welfare decreases as the prior becomes stronger, and welfare always decreases as the signals become less correlated.

Information acquisition in committees

Dino Gerardi — 2008-04-23T19:01:58-00:00

Games and Economic Behavior, Vol. 62, No. 2. (March 2008), pp. 436-459.

The goal of this paper is to illustrate the significance of information acquisition in mechanism design. We provide a stark example of a mechanism design problem in a collective choice environment with information acquisition. We concentrate on committees that are comprised of agents sharing a common goal and having a joint task. Members of the committee decide whether to acquire costly information or not at the outset and are then asked to report their private information. The designer can choose the size of the committee, as well as the procedure by which it selects the collective choice, i.e., the correspondence between agents' reports and distributions over collective choices. We show that the ex ante optimal device may be ex post inefficient, i.e., lead to suboptimal aggregation of information from a statistical point of view. For particular classes of parameters, we describe the full structure of the optimal mechanisms.

Voting Behavior and Information Aggregation in Elections With Private Information

Timothy Feddersen — 2008-07-01T07:16:00-00:00

Econometrica, Vol. 65, No. 5. (1997), pp. 1029-1058.

We analyze two-candidate elections in which voters are uncertain about the realization of a state variable that affects the utility of all voters. Each voter has noisy private information about the state variable. We show that the fraction of voters whose vote depends on their private information goes to zero as the size of the electorate goes to infinity. Nevertheless, elections fully aggregate information in the sense that the chosen candidate would not change if all private information were common knowledge. Equilibrium voting behavior is to a large extent determined by the electoral rule, i.e., if a candidate is required to get at least x percent of the vote in order to win the election, then in equilibrium this candidate gets very close to x percent of the vote with probability close to one. Finally, if the distribution from which preferences are drawn is uncertain, then elections will generally not satisfy full information equivalence and the fraction of voters who take informative action does not converge to zero.

A Bayesian Model of Voting in Juries

John Duggan — 2005-02-23T15:13:13-00:00

Games and Economic Behavior, Vol. 37, No. 2. (November 2001), pp. 259-294.

We model voting in juries as a game of incomplete information, allowing jurors to receive a continuum of signals. We characterize the unique symmetric equilibrium of the game, and give a condition under which no asymmetric equilibria exist under unanimity rule. We offer a condition under which unanimity rule exhibits a bias toward convicting the innocent, regardless of the size of the jury, and give an example showing that this bias can be reversed. We prove a "jury theorem" for our general model: As the size of the jury increases, the probability of a mistaken judgment goes to zero for every voting rule except unanimity rule. For unanimity rule, the probability of making a mistake is bounded strictly above zero if and only if there do not exist arbitrarily strong signals of innocence. Our results explain the asymptotic inefficiency of unanimity rule in finite models and establishes the possibility of asymptotic efficiency, a property that could emerge only in a continuous model. Journal of Economic Literature Classification Numbers: C72, D72.

Information Aggregation, Rationality, and the Condorcet Jury Theorem

David Austen-Smith — 2008-07-01T04:18:23-00:00

The American Political Science Review, Vol. 90, No. 1. (1996), pp. 34-45.

The Condorcet Jury Theorem states that majorities are more likely than any single individual to select the "better" of two alternatives when there exists uncertainty about which of the two alternatives is in fact preferred. Most extant proofs of this theorem implicitly make the behavioral assumption that individuals vote "sincerely" in the collective decision making, a seemingly innocuous assumption, given that individuals are taken to possess a common preference for selecting the better alternative. However, in the model analyzed here we find that sincere behavior by all individuals is not rational even when individuals have such a common preference. In particular, sincere voting does not constitute a Nash equilibrium. A satisfactory rational choice foundation for the claim that majorities invariably "do better" than individuals, therefore, has yet to be derived.

Incentives, Information, and Organizational Form

Eric Maskin — 2008-07-01T15:19:45-00:00

The Review of Economic Studies, Vol. 67, No. 2. (2000), pp. 359-378.

We model an organization as a hierarchy of managers erected on top of a technology (here consisting of a collection of plants). In our framework, the role of a manager is to take steps to reduce the adverse consequences of shocks that affect the plants beneath him. We argue that different organizational forms give rise to different information about managers' performance and therefore differ according to how effective incentives can be in encouraging a good performance. In particular, we show that, under certain assumptions, the M-form (multi-divisional form) is likely to provide better incentives than the U-form (unitary form) because it promotes yardstick competition (i.e. relative performance evaluation) more effectively. We conclude by presenting evidence that the assumptions on which this comparison rests are satisfied for Chinese data.

Monopoly Agenda Control and Asymmetric Information

Jeffrey Banks — 2008-07-02T13:24:35-00:00

The Quarterly Journal of Economics, Vol. 105, No. 2. (1990), pp. 445-464.

This paper extends the Romer-Rosenthal [1978, 1979] model of monopoly agenda control to an environment where only the agenda setter knows with certainty the outcome associated with a failed proposal. The presence of this asymmetric information implies that any "take-it-or-leave-it" proposal may provide information crucial to the decision calculus of the voters, a fact which an optimal proposal strategy will incorporate. The equilibrium behavior of the agenda setter and voters is characterized and contrasted with that in the complete information environment, and a number of empirical predictions concerning the nature of elections with monopoly controlled agendas are derived.

Voting as Communicating

Thomas Piketty — 2008-07-01T12:11:38-00:00

The Review of Economic Studies, Vol. 67, No. 1. (2000), pp. 169-191.

This paper develops a model where voters trade-off two different motives when deciding how to vote: they care about current decision-making (they are "strategic"), but they also care about communicating their views about their most-preferred candidate so as to influence future elections, by influencing other voters' opinion and/or party positioning. In effect, voters in this model are intermediate between "strategic" and "sincere" voters of conventional models in elections with more than 2 candidates. This allows us to better investigate the relative efficiency of various electoral systems: our main conclusion is that since voting is used as a communication device electoral systems should be designed to facilitate efficient communication, e.g. by opting for 2-round systems rather than 1-round systems.

The information-aggregation approach to political institutions

Thomas Piketty — 2008-07-01T12:09:07-00:00

European Economic Review, Vol. 43, No. 4-6. (April 1999), pp. 791-800.

This paper offers a short survey of recent contributions about the information-aggregation role of political institutions. We argue that these recent developments represent a promising come-back to the Condorcet's original approach to political economy and allow to renew the efficiency analysis of alternative political institutions. In the same way as in the economic literature on the price system and the informational rationale for non-market insitutions such as firms, this recent literature that the basic efficiency of majority-rule voting and other electoral systems needs to be complemented by non-voting political institutions such as political parties, public debate and polls.

Committee Design with Endogenous Information

N Persico — 2008-07-01T11:58:18-00:00

The Review of Economic Studies (January 2004), pp. 165-191.

Identical agents gather costly information, and then aggregate it through voting.Because information is a public good, information is underprovided relative to thesocial optimum. A “good” voting rule must give incentives to acquire information,as well as aggregate information efficiently. A voting rule that requires a largeplurality (in the extreme, unanimity) to upset the status quo can be optimal onlyif the information available to each agent is sufficiently accurate. This result isindependent of the preferences of voters and of the cost of information.

Informational origins of political bias towards critical groups of voters

Roger Myerson — 2008-07-01T10:53:52-00:00

European Economic Review, Vol. 43, No. 4-6. (April 1999), pp. 767-778.

We show how non-symmetric politicization can arise in a democracy where voters are distributed across several ex-ante symmetric sectors. The voters are uncertain about the administrative ability of an elected official. They observe the quality of her performance, which depends on her ability and her effort. The official can allocate her efforts symmetrically or non-symmetrically across sectors. We show the existence of a non-symmetric equilibrium, in which the official allocates more effort to administering one critical sector, because voters in other sectors rationally respond less to what they observe about the quality of to her administration.

Information Flow in Social Groups

Fang Wu — 2005-09-05T11:51:28-00:00

(22 May 2003)

We present a study of information flow that takes into account the observation that an item relevant to one person is more likely to be of interest to individuals in the same social circle than those outside of it. This is due to the fact that the similarity of node attributes in social networks decreases as a function of the graph distance. An epidemic model on a scale-free network with this property has a finite threshold, implying that the spread of information is limited. We tested our predictions by measuring the spread of messages in an organization and also by numerical experiments that take into consideration the organizational distance among individuals.

Information Dynamics in the Networked World

Bernardo Huberman — 2006-04-24T12:03:10-00:00

(13 Oct 2003)

We review three studies of information flow in social networks that help reveal their underlying social structure, how information spreads through them and why small world experiments work.

What is complexity?

C Adami — 2005-05-19T10:35:54-00:00

Bioessays, Vol. 24, No. 12. (December 2002), pp. 1085-1094.

Arguments for or against a trend in the evolution of complexity are weakened by the lack of an unambiguous definition of complexity. Such definitions abound for both dynamical systems and biological organisms, but have drawbacks of either a conceptual or a practical nature. Physical complexity, a measure based on automata theory and information theory, is a simple and intuitive measure of the amount of information that an organism stores, in its genome, about the environment in which it evolves. It is argued that physical complexity must increase in molecular evolution of asexual organisms in a single niche if the environment does not change, due to natural selection. It is possible that complexity decreases in co-evolving systems as well as at high mutation rates, in sexual populations, and in time-dependent landscapes. However, it is reasoned that these factors usually help, rather than hinder, the evolution of complexity, and that a theory of physical complexity for co-evolving species will reveal an overall trend towards higher complexity in biological evolution.

Web Usage Mining Using Artificial Ant Colony Clustering And Genetic Programming

Vitorino Ramos — 2005-10-25T11:12:23-00:00

The rapid e-commerce growth has made both business community and customers face a new situation. Due to intense competition on one hand and the customer's option to choose from several alternatives business community has realized the necessity of intelligent marketing strategies and relationship management. Web usage mining attempts to discover useful knowledge from the secondary data obtained from the interactions of the users with the Web. Web usage mining has become very critical for...

Swarms on Continuous Data

Vitorino Ramos — 2005-11-24T18:26:19-00:00

While being it extremely important, many Exploratory Data Analysis (EDA [21]) systems have the inhability to perform classification and visualization in a continuous basis or to self-organize new data-items into the older ones (evenmore into new labels if necessary), which can be crucial in KDD - Knowledge Discovery [10,1], Retrieval and Data Mining Systems [15,10] (interactive and online forms of Web Applications are just one example). This disadvantge is also present in more recent approaches ...

A note about entropy

Eliahu Levy — 2006-02-10T12:04:07-00:00

(9 Feb 2006)

A mathematical interpretation of the usual definition of entropy (for a discrete probability distribution or a trace 1 positive operator) is given. This formulation makes some properties of entropy immediate.

Serendipity and information seeking: an empirical study

A Foster — 2004-11-23T06:24:03-00:00

Journal of Documentation, Vol. 59, No. 3. (7 May 2003), pp. 321-340.

"Serendipity" has both a classical origin in literature and a more modern manifestation where it is found in the descriptions of the problem solving and knowledge acquisition of humanities and science scholars. Studies of information retrieval and information seeking have also discussed the utility of the notion of serendipity. Some have implied that it may be stimulated, or that certain people may "encounter" serendipitous information more than others. All to some extent accept the classical definition of serendipity as a "fortuitous" accident. The analysis presented here is part of a larger study concerning the information-seeking behaviour of interdisciplinary scholars. This paper considers the nature of serendipity in information-seeking contexts, and reinterprets the notion of serendipity as a phenomenon arising from both conditions and strategies - as both a purposive and a non-purposive component of information seeking and related knowledge acquisition.

Shannon Information and Kolmogorov Complexity

Peter Grunwald — 2004-11-22T00:17:30-00:00

(1 October 2004)

We compare the elementary theories of Shannon information and Kolmogorov complexity, the extent to which they have a common purpose, and where they are fundamentally different. We discuss and relate the basic notions of both theories: Shannon entropy versus Kolmogorov complexity, the relation of both to universal coding, Shannon mutual information versus Kolmogorov (`algorithmic') mutual information, probabilistic sufficient statistic versus algorithmic sufficient statistic (related to lossy compression in the Shannon theory versus meaningful information in the Kolmogorov theory), and rate distortion theory versus Kolmogorov's structure function. Part of the material has appeared in print before, scattered through various publications, but this is the first comprehensive systematic comparison. The last mentioned relations are new.

Thermodynamical Quantum Information Sharing

M Wiesniak — 2005-03-04T05:52:10-00:00

(3 March 2005)

We show that, when measured along orthogonal spatial directions, magnetic susceptibility can reveal entanglement between individual constituents of a solid, while magnetisation describes their local properties. We then show that these two thermodynamical quantities satisfy complementary relation in the quantum-mechanical sense. It describes sharing of (quantum) information in the solid between entanglement and local properties of its individual constituents. Magnetic susceptibility is shown to be universal macroscopic entanglement witness that can be applied independently of the model of the solid (without the knowledge of its Hamiltonian).

Quantum information can be negative

Michal Horodecki — 2005-08-09T18:29:54-00:00

(9 May 2005)

Given an unknown quantum state distributed over two systems, we determine how much quantum communication is needed to transfer the full state to one system. This communication measures the "partial information" one system needs conditioned on it's prior information. It turns out to be given by an extremely simple formula, the conditional entropy. In the classical case, partial information must always be positive, but we find that in the quantum world this physical quantity can be negative. If the partial information is positive, its sender needs to communicate this number of quantum bits to the receiver; if it is negative, the sender and receiver instead gain the corresponding potential for future quantum communication. We introduce a primitive "quantum state merging" which optimally transfers partial information. We show how it enables a systematic understanding of quantum network theory, and discuss several important applications including distributed compression, multiple access channels and multipartite assisted entanglement distillation (localizable entanglement). Negative channel capacities also receive a natural interpretation.