36 resultados para Number Theory
Resumo:
Any attempt to model an economy requires foundational assumptions about the relations between prices, values and the distribution of wealth. These assumptions exert a profound influence over the results of any model. Unfortunately, there are few areas in economics as vexed as the theory of value. I argue in this paper that the fundamental problem with past theories of value is that it is simply not possible to model the determination of value, the formation of prices and the distribution of income in a real economy with analytic mathematical models. All such attempts leave out crucial processes or make unrealistic assumptions which significantly affect the results. There have been two primary approaches to the theory of value. The first, associated with classical economists such as Ricardo and Marx were substance theories of value, which view value as a substance inherent in an object and which is conserved in exchange. For Marxists, the value of a commodity derives solely from the value of the labour power used to produce it - and therefore any profit is due to the exploitation of the workers. The labour theory of value has been discredited because of its assumption that labour was the only ‘factor’ that contributed to the creation of value, and because of its fundamentally circular argument. Neoclassical theorists argued that price was identical with value and was determined purely by the interaction of supply and demand. Value then, was completely subjective. Returns to labour (wages) and capital (profits) were determined solely by their marginal contribution to production, so that each factor received its just reward by definition. Problems with the neoclassical approach include assumptions concerning representative agents, perfect competition, perfect and costless information and contract enforcement, complete markets for credit and risk, aggregate production functions and infinite, smooth substitution between factors, distribution according to marginal products, firms always on the production possibility frontier and firms’ pricing decisions, ignoring money and credit, and perfectly rational agents with infinite computational capacity. Two critical areas include firstly, the underappreciated Sonnenschein-Mantel- Debreu results which showed that the foundational assumptions of the Walrasian general-equilibrium model imply arbitrary excess demand functions and therefore arbitrary equilibrium price sets. Secondly, in real economies, there is no equilibrium, only continuous change. Equilibrium is never reached because of constant changes in preferences and tastes; technological and organisational innovations; discoveries of new resources and new markets; inaccurate and evolving expectations of businesses, consumers, governments and speculators; changing demand for credit; the entry and exit of firms; the birth, learning, and death of citizens; changes in laws and government policies; imperfect information; generalized increasing returns to scale; random acts of impulse; weather and climate events; changes in disease patterns, and so on. The problem is not the use of mathematical modelling, but the kind of mathematical modelling used. Agent-based models (ABMs), objectoriented programming and greatly increased computer power however, are opening up a new frontier. Here a dynamic bargaining ABM is outlined as a basis for an alternative theory of value. A large but finite number of heterogeneous commodities and agents with differing degrees of market power are set in a spatial network. Returns to buyers and sellers are decided at each step in the value chain, and in each factor market, through the process of bargaining. Market power and its potential abuse against the poor and vulnerable are fundamental to how the bargaining dynamics play out. Ethics therefore lie at the very heart of economic analysis, the determination of prices and the distribution of wealth. The neoclassicals are right then that price is the enumeration of value at a particular time and place, but wrong to downplay the critical roles of bargaining, power and ethics in determining those same prices.
Resumo:
This paper represents a first attempt to provide an integrated framework to explain the onset, development, and maintenance of sexual offending. According to the Integrated Theory of Sexual Offending (ITSO), sexual abuse occurs as a consequence of a number of interacting causal variables. We examine the factors that affect brain development (evolution, genetic variations and neurobiology) and ecological factors (social and cultural environment, personal circumstances, physical environment) and discuss how they impact upon core neuropsychological functions underpinning human action. The ITSO then explains how clinical symptoms arise from the interaction between these neurological systems and ecological factors. The capacity of the ITSO to incorporate competing theories of sexual offending is considered, and we end the paper by critically evaluating its usefulness in stimulating research and further theory development.
Resumo:
Light scattering from small spherical particles has applications in a vast number of disciplines including astrophysics, meteorology optics and particle sizing. Mie theory provides an exact analytical characterization of plane wave scattering from spherical dielectric objects. There exist many variants of the Mie theory where fundamental assumptions of the theory has been relaxed to make generalizations. Notable such extensions are generalized Mie theory where plane waves are replaced by optical beams, scattering from lossy particles, scattering from layered particles or shells and scattering of partially coherent (non-classical) light. However, no work has yet been reported in the literature on modifications required to account for scattering when the particle or the source is in motion relative to each other. This is an important problem where many applications can be found in disciplines involving moving particle size characterization. In this paper we propose a novel approach, using special relativity, to address this problem by extending the standard Mie theory for scattering by a particle in motion with a constant speed, which may be very low, moderate or comparable to the speed of light. The proposed technique involves transforming the scattering problem to a reference frame co-moving with the particle, then applying the Mie theory in that frame and transforming the scattered field back to the reference frame of the observer.
Resumo:
Measurements have been made of the solvation forces between mica surfaces in the even-numbered n-alkanes from hexane to hexadecane. In all cases the force law is qualitatively very similar, characterized by a decaying oscillatory function of distance, as occurs for simple isotropic liquids. The spacing between successive minima in the force does not increase with carbon number, and is comparable to the width of a linear alkane molecule rather than its length or any average diameter. This suggests that the alkanes have some tendency towards a parallel orientation near the mica surfaces. The measurements give no indication of any strong repulsive component expected from mean-field theories of higher alkanes or polymers. The results of one such theory are presented, and the reasons for its failure to match the experimental data are discussed.
Resumo:
This paper reviews the work published in JMTP during its first 20 years. It finds extensive global coverage in terms of authors and material, despite a U.S. emphasis. In addition, a diversity of topics is covered and is making a significant contribution, as defined by citations, to broader academic discourse. The works published have a strong applied focus, although this might be expected to have been higher given the journal's applied foundations. The paper also identifies the most prolific individuals and institutions, based on the number of articles published and citations to those articles. The paper concludes that JMTP has made a valuable contribution to marketing academia and its global recognition continues to grow.
Resumo:
Despite the frequency with which the concept of neoliberalism is employed within academic literature, its complex and multifaceted nature makes it difficult to define and describe. Indeed, data reported in this article suggest that there is a tendency in educational research to make extensive use of the word ‘neoliberalism’ (or its variants neoliberal, neo-liberal and neo-liberalism) as a catch-all for something negative but without offering a definition or explanation. The article highlights a number of key risks associated with this approach and draws on the Bourdieuian concept of illusio to suggest the possibility that when as educational researchers we use the word ‘neoliberalism’ in this way, rather than interrupting the implementation of neoliberal policies and practices, we may, in fact, be further entrenching the neoliberal doxa. That is to say, we are both playing the neoliberal game and inadvertently demonstrating our belief that it is a game worth being played. In so doing, this article seeks to extend understandings of what illusio means within the context of educational research.
Resumo:
This article reports on a study into university preservice teachers’ perceptions of online video-recorded interviews as an alternative to the traditional lecture format in a course on inclusive education. With the aim of assisting preservice teachers to link theory and practice, the series of video-recorded interviews focused on key concepts around educating students with diverse needs and abilities. The interviews were conducted between the course coordinator and a number of professionals with relevant field experience in special education and inclusion, and were then made available to preservice teachers online. Survey data indicated that this type of delivery model was perceived as effective in promoting engagement and learning, and in facilitating an understanding of the connection between theory and practice. Implications for teacher education are discussed.
Resumo:
There is growing interest in the concept of ‘‘mechanism’’ across many areas of the social sciences. In the field of program and policy evaluation, a number of scholars have also emphasized the importance of causal mechanisms for explaining how and why programs work. However, there appears to be some ambiguity about the meaning and uses of mechanism-based thinking in both the social science and evaluation literature. In this article we attempt to clarify what is meant by mechanisms in the context of program evaluation by identifying three main characteristics of mechanisms and outlining a possible typology of mechanisms. A number of theoretical and practical implications for evaluators are also discussed, along with some precautions to consider when investigating mechanisms that might plausibly account for program outcomes.
Resumo:
This paper reports on a study into pre-service teachers’ perceptions about their professional development during practicum. The study examined to what extent, and how effectively, one group of pre-service teachers was able to integrate theory and practice during a three-week practicum in the first year of their degree. Data for this mixed methods study were drawn from one cohort of first-year students undertaking the Master of Teaching (MTeach), a graduate-level entry program in the Faculty of Education at an urban Australian university. Although there is a strong field of literature around the practicum in pre-service teacher education, there has been a limited focus on how pre-service teachers themselves perceive their development during this learning period. Further, despite widespread and longstanding acknowledgement of the “gap” between theory and practice in teacher education, there is still more to learn about how well the practicum enables an integration of these two dimensions of teacher preparation. In presenting three major findings of the study, this paper goes some way in addressing these shortcomings in the literature. First, opportunities to integrate theory and practice were varied, with many participants reporting supervision and scheduling issues as impacting on their capacity to effectively enact theory in practice. Second, participants’ privileging of theory over practice, identified previously in the literature as commonly characteristic of the pre-service teacher, was found in this study to be particularly prevalent during practicum. Third, participants overwhelmingly supported the notion of linking university coursework assessment to the practicum as a means of bridging the gap between, on the one hand, the university and the school and, on the other hand, theory and practice. The discussion and consideration of findings such as those reported in this paper are pertinent and timely, given the ratification of both the National Professional Standards for Teachers and the Initial Teacher Education Program Standards by the Australian Federal Government earlier this year. Within a number of the seven Professional Standards, graduate teachers are required to demonstrate knowledge and skills associated with both the theory and practice of teaching and with their effective integration in the classroom. To be nationally accredited, pre-service teacher education programs must provide evidence of enabling pre-service teachers to acquire such knowledge and skills.
Intervention efficacy among 'At Risk' adolescents: a test of subjective wellbeing homeostasis theory
Resumo:
This study tests a number of theoretical predictions based on subjective wellbeing (SWB) Homeostasis Theory. This theory proposes that SWB is actively maintained and defended within a narrow, positive range of values around a 'set-point' for each person. Due to homeostatic control, it is predicted to be very difficult to substantially increase SWB in samples operating normally within their set-point-range. However, under conditions of homeostatic defeat, where SWB is lower than normal, successful interventions should be accompanied by a substantial increase as each person's SWB returns to lie within its normal range of values. This study tests these propositions using a sample of 4,243 participants in an Australian Federal Government Program for 'at-risk' adolescents. SWB was measured using the Personal Wellbeing Index and results are converted to a metric ranging from 0 to 100 points. The sample was divided into three sub-groups as 0-50, 51-69, and 70+ points. The theoretical prediction was confirmed. The largest post-intervention increase in SWB was in the 0-50 group and lowest in the 70+ group. However, a small increase in SWB was observed in the normal group, which was significant due to the large sample size. The implications of these findings for governments, schools and policy makers are discussed.
Resumo:
Research question:
Research methods:
Employing a grounded theory method and drawing on the analysis and synthesis of 32 interviews and 25 organisational documents, this research explored managerial decision-making with regard to CSR in English football.
Results and findings:
The findings reveal that decision-making consists of four simultaneous micro-social processes (‘harmonising’, ‘safeguarding’, ‘manoeuvring’ and ‘transcending’) that form the platform upon which the managers in the charitable foundations of the English football clubs make decisions. These four micro-social processes together represent assessable transcendence; a process that is fortified by passion, contingent on trust, sustained by communication and substantiated by factual performance enables CSR formulation and implementation in this organisational context.
Implications:
The significance of this study for the sport management literature is threefold: (1) it focuses on the individual level of analysis, (2) it shifts the focus of the scholarly activity away from CSR content-based research towards more processoriented approaches and (3) it adds to the limited number of studies that have utilised grounded theory in a rounded manner.
Resumo:
Measurement reactivity effects, such as the mere measurement effect, have been proposed as a reason for behavioural changes in a number of theory of planned behaviour intervention studies. However, it is unclear whether such changes are the result of the mere measurement effect or of other artefacts of intervention study design. The aim of this study is to determine the size and direction of changes in health behaviours from baseline to follow-up in prospective studies using the theory of planned behaviour. Electronic databases were searched for the theory of planned behaviour studies which measured health behaviours at two or more time points. Change in behaviour was calculated for all studies. Sixty-six studies were included. Mean effect sizes across all studies were small and negative (d = -.03). Effect size was moderated by behaviour, behaviour type and follow-up length. Subgroup analyses showed significant decreases in socially undesirable behaviour (d = -.28), binge drinking (d = -.17), risk driving (d = -.20), sugar snack consumption (d = -.43) and sun-protective behaviour (d = -.18). Measurement of intention at baseline resulted in significant decreases in undesirable behaviour. Changes in undesirable behaviours reported in other studies may be the result of the mere measurement effect.
Resumo:
The practical, normative dimension of planning is a plausible source of the ‘family resemblances’ noted by a number of legal theorists between Scott Shapiro’s Planning Theory and natural law jurisprudence. Foremost among these resemblances is Shapiro’s contention that the law, necessarily, has a moral aim. The moral aim thesis is at first glance surprising given Shapiro’s intention to defend exclusive legal positivism and unequivocal rejection of what he takes to be the core commitments of natural law theory. Shapiro’s claim, however, is that although the law necessarily has a moral aim, this does not entail that it is successful in satisfying that aim. In order to assess this thesis, it is helpful to compare the Planning Theory with contemporary natural law approaches. Bringing Shapiro’s Planning Theory into dialogue with contemporary natural law theories can demonstrate some of the Planning Theory’s weaknesses as an alternative explanation of the ultimate grounds of the authoritativeness of legal norms. Some of these weaknesses, moreover, are instructive beyond the specific contours of the Planning Theory insofar as they generalise to other legal positivist approaches. In section one I consider Shapiro’s treatment of the so-called ‘Possibility Puzzle’ regarding the grounding relation between authoritative norms and legal authority. Shapiro’s denial of the capacity of earlier jurisprudential theories to resolve this puzzle overlooks what is – I suggest – a plausible solution developed by John Finnis on the basis of Joseph Raz’s theory of practical reason and norms. Section two then demonstrates why Shapiro’s attempt to combine a robust construal of the social facts thesis with a commitment to the thesis that law necessarily has a moral aim is ultimately unsuccessful.
Resumo:
This paper critically analyzes the use of Absorptive Capacity (ACAP) theory in information systems (IS) research. Drawing on a comprehensive review of the evolution of ACAP theory and models for the construct, we empirically investigate a number of ACAP-related papers published in reputable IS journals. The analysis involves four main areas: 1) summary analysis of ACAP in IS papers; 2) domains of ACAP usage; 3) analysis of hypotheses to show how ACAP is being used to explain various organizational phenomena in IS research; and 4) analysis of measures to gain insights into the operationalization of ACAP in IS research. This research advocates that organization-level ACAP should be applied as the dependent variable in studying the impact of IS. Furthermore, ACAP should be conceptualized as a “capability,” rather than an “asset.” This paper contributes to IS and ACAP studies by investigating and clearly specifying the utility of ACAP in IS research.
A general theory of tourism consumption systems: a conceptual framework and an empirical exploration
Resumo:
A tourism consumption system (TCS) is defined as the setof related travel thoughts, decisions, and behaviors by a discretionarytraveler prior to, during, and following a trip. Thecentral proposition of a theory of TCS is that the thoughts,decisions, and behaviors regarding one activity influence thethoughts, decisions, and behaviors for a number of other activities.Using exit interview travel data and quick clusteringanalysis, this article empirically examines seven basic TCSpropositions pertaining to decisions made once the destinationhas been selected. The findings support and extend thebasic propositions specifically indicating clear patterns inthe behaviors of visitors to Prince Edward Island, Canada.The authors conclude by recommending that this approach isuseful for tourism marketers and practitioners in general.Suggestions are provided for analyzing TCS to increase theeffectiveness of tourism marketing strategies.