The Grip of History and the Scope for Novelty: Some Results and Open Questions on Path Dependence in Economic Processes

-Path dependence, irreversibility, increasing returns, learning, lock-in.

Agent-Based Computational Economics

Agent-based computational economics (ACE) is the computational study of economies modeled as evolving systems of autonomous interacting agents. Starting from initial conditions, specified by the modeler, the computational economy evolves over time as its constituent agents repeatedly interact with each other and learn from these interactions. ACE is therefore a bottom-up culture-dish approach to the study of economic systems. This study discusses the key characteristics and goals of the ACE methodology. Eight currently active research areas are highlighted for concrete illustration. Potential advantages and disadvantages of the ACE methodology are considered, along with open questions and possible directions for future research.Agent-based computational economics; Autonomous agents; Interaction networks; Learning; Evolution; Mechanism design; Computational economics; Object-oriented programming.

Generalized Domination.

This thesis develops the theory of the everywhere domination relation between functions from one infinite cardinal to another. When the domain of the functions is the cardinal of the continuum and the range is the set of natural numbers, we may restrict our attention to nicely definable functions from R to N. When we consider a class of such functions which contains all Baire class one functions, it becomes possible to encode information into these functions which can be decoded from any dominator. Specifically, we show that there is a generalized Galois-Tukey connection from the appropriate domination relation to a classical ordering studied in recursion theory. The proof techniques are developed to prove new implications regarding the distributivity of complete Boolean algebras. Next, we investigate a more technical relation relevant to the study of Borel equivalence relations on R with countable equivalence classes. We show than an analogous generalized Galois-Tukey connection exists between this relation and another ordering studied in recursion theory.PhDMathematicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113539/1/danhath_1.pd

The international centre for theoretical physics, 1960-1979 : ideology and practice in a United Nations institution for scientific co-operation and third world development

In this work the history of the establishment of the International Centre for Theoretical Physics in Trieste is studied with particular attention to its first director Abdus Salam and the dynamics of international co-operation in science during its foundation and early years. Some aspects of Salam's social, religious and cultural background, as well as his Cambridge training in physics and mathematics are discussed as essential elements in motivating and enabling his career as a scientific diplomat and administrator. It is argued that although Salam managed to provide an effective justification for the creation and existence of the Centre, the majority of the industrialised countries, as well as the Socialist countries, opposed the initiative. The negotiation process for the creation of the ICTP is studied in detail highlighting the crucial role played by Italy and Trieste. It is also argued that institutional instability created by a lack of both financial support and a permanent scientific staff recognised by the scientific elite undermined the status of the institution as well as the work carried out within its walls. Two contrasting images of the Centre prevailed throughout the period studied: for the elite among the scientific community in the industrialised countries, it was a United Nations development institute for the education of Third World scientists, whereas in the developing countries it was perceived as a scientific centre for mainstream research. The fund-raising strategies, based on the cultivation of a network of personal contacts around the world are discussed, focusing on the relation between the ICTP and the Ford Foundation. Finally, the everyday operation of the ICTP as an academic institution is studied. This entails a discussion of the scientific population of the Centre as well as an analysis of the activities carried out there in terms of training and research. The effect of the ICTP on Salam’s scientific work and the influence of Salam on some features of the ICTP’s scientific practices are also discussed in detail. The history of the ICTP stands as an excellent case study in the contrast that can exist between public rhetoric regarding scientific collaboration between unequal international partners and the reality of that collaboration

Computational Explorations of Creativity and Innovation in Design

This thesis addresses creativity in design as a property of systems rather than an attribute of isolated individuals. It focuses on the dynamics between generative and evaluative or ascriptive processes. This is in distinction to conventional approaches to the study of creativity which tend to concentrate on the isolated characteristics of person, process and product. Whilst previous research has advanced insights on potentially creative behaviour and on the general dynamics of innovation in groups, little is known about their interaction. A systems view of creativity in design is adopted in our work to broaden the focus of inquiry to incorporate the link between individual and collective change. The work presented in this thesis investigates the relation between creativity and innovation in computational models of design as a social construct. The aim is to define and implement in computer simulations the different actors and components of a system and the rules that may determine their behaviour and interaction. This allows the systematic study of their likely characteristics and effects when the system is run over simulated time. By manipulating the experimental variables of the system at initial time the experimenter is able to extract patterns from the observed results over time and build an understanding of the different types of determinants of creative design. The experiments and findings presented in this thesis relate to artificial societies composed by software agents and the social structures that emerge from their interaction. Inasmuch as these systems aim to capture some aspects of design activity, understanding them is likely to contribute to the understanding of the target system. The first part of this thesis formulates a series of initial computational explorations on cellular automata of social influence and change agency. This simple modelling framework illustrates a number of factors that facilitate change. The potential for a designer to trigger cycles of collective change is demonstrated to depend on the combination of individual and external or situational characteristics. A more comprehensive simulation framework is then introduced to explore the link between designers and their societies based on a systems model of creativity that includes social and epistemological components. In this framework a number of independent variables are set for experimentation including characteristics of individuals, fields, and domains. The effects of these individual and situational parameters are observed in experimental settings. Aspects of relevance in the definition of creativity included in these studies comprise the role of opinion leaders as gatekeepers of the domain, the effects of social organisation, the consequences of public and private access to domain knowledge by designers, and the relation between imitative behaviour and innovation. A number of factors in a social system are identified that contribute to the emergence of phenomena that are normally associated to creativity and innovation in design. At the individual level the role of differences of abilities, persistence, opportunities, imitative behaviour, peer influence, and design strategies are discussed. At the field level determinants under inspection include group structure, social mobility and organisation, emergence of opinion leaders, established rules and norms, and distribution of adoption and quality assessments. Lastly, domain aspects that influence the interaction between designers and their social groups include the generation and access to knowledge, activities of gatekeeping, domain size and distribution, and artefact structure and representation. These insights are discussed in view of current findings and relevant modelling approaches in the literature. Whilst a number of assumptions and results are validated, others contribute to ongoing debates and suggest specific mechanisms and parameters for future experimentation. The thesis concludes by characterising this approach to the study of creativity in design as an alternative 'in silico' method of inquiry that enables simulation with phenomena not amenable to direct manipulation. Lines of development for future work are advanced which promise to contribute to the experimental study of the social dimensions of design

Fast water streams deflected by transverse walls

Imperial Users onl

Green visions and democratic constraints: the possibility and design of democratic institutions for environmental decision-making

This thesis addresses a recurrent question of our time – whether democracy can secure environmental sustainability – by drawing on literatures in the normative theory of democracy, social choice theory and environmental politics. I propose a basic, yet substantial organising principle, the ‘dilemma of green democracy’, which maps out the possibility of realising green outcomes under democratic constraints. Interdisciplinary ideas from neighbouring disciplines are also imported for the purpose of studying the design of good environmental-democratic institutions. The analytical framework is an integrated one, comprising formal choice theory and normative democratic theory. The first part of the thesis focuses on the possibility of environmentaldemocratic institutions. Chapter 1 introduces the dilemma of green democracy – a conflict between three plausible desiderata for environmental democracy – and suggests several proposals for avoiding the dilemma. It concludes that, as long as the dilemma is resolved, it is logically possible to construct environmental-democratic institutions. Chapters 2, 3 and 4 assess the desirability of the different proposals in terms of procedure and outcome. The general conclusion is that whether these proposals are desirable depends on a number of conditions and/or contextual factors. The second part of the thesis examines the substantive issues in designing environmental-democratic institutions. Chapter 5 discusses how the discursive dilemma in social choice theory and the normative ends of deliberation constrain the inputs of such institutions. Chapter 6 demonstrates how the concept of distributed cognition, drawn from cognitive/computer science, reconciles the tension between technocracy and democracy. Chapter 7 suggests how the theory of cognitive dissonance, drawn from psychology, challenges the epistemic performance of practicable (environmental-) deliberative-democratic institutions. The overall conclusion is two-fold. First, democracy can, at least in principle, secure environmental sustainability, provided that the dilemma of green democracy is resolved. Second, interdisciplinary ideas are useful for designing good democratic institutions for collective environmental decision-making. This conclusion has implications not only for intellectual enquiry, but also for institutional design in practice