768 resultados para learning theory
Resumo:
This paper argues for the need to further theorise the concept of teacher professional learning communities and provides empirical evidence to support this case. The paper presents findings from an ongoing research project, which investigates the nature of teacher professional learning communities. The study reveals that actual communities do not conform to a normailized articulation of features, as outlined in much of the literature on this topic. Consequently, it represents an attempt to engage in the difficult but necessary task of simultaneously fashioning theory from practice, whilst interpreting theory, in practice. The study proposes that current functionalist understandings of teacher professional learning communities are based upon a literature base which is insufficiently nuanced to capture the complexity inherent within these bodies. A broader base of a more critical sociological literature is also drawn upon to better understand actual, "lived" teacher communities, which are somewhat difficult to describe. In part, such communities exhibit features of functionalist conceptions but they are also organic entities which may be quite unpredictable in their outcomes and cannot be reduced to specific features; they each have their own specific "logic of practice" (Bourdieu, 1990) which influences their activities, in their particular field. The argument proposed here is that in one particular community, this complexity may be represented by the many purposes which the community served, arguably often unbeknown to its members, which fashioned the actual community. This paper tries to add to the existing theoretical base of literature, at the same time as providing evidence to support this theorisation.
Resumo:
A formalism for describing the dynamics of Genetic Algorithms (GAs) using method s from statistical mechanics is applied to the problem of generalization in a perceptron with binary weights. The dynamics are solved for the case where a new batch of training patterns is presented to each population member each generation, which considerably simplifies the calculation. The theory is shown to agree closely to simulations of a real GA averaged over many runs, accurately predicting the mean best solution found. For weak selection and large problem size the difference equations describing the dynamics can be expressed analytically and we find that the effects of noise due to the finite size of each training batch can be removed by increasing the population size appropriately. If this population resizing is used, one can deduce the most computationally efficient size of training batch each generation. For independent patterns this choice also gives the minimum total number of training patterns used. Although using independent patterns is a very inefficient use of training patterns in general, this work may also prove useful for determining the optimum batch size in the case where patterns are recycled.
Resumo:
A theoretical model is presented which describes selection in a genetic algorithm (GA) under a stochastic fitness measure and correctly accounts for finite population effects. Although this model describes a number of selection schemes, we only consider Boltzmann selection in detail here as results for this form of selection are particularly transparent when fitness is corrupted by additive Gaussian noise. Finite population effects are shown to be of fundamental importance in this case, as the noise has no effect in the infinite population limit. In the limit of weak selection we show how the effects of any Gaussian noise can be removed by increasing the population size appropriately. The theory is tested on two closely related problems: the one-max problem corrupted by Gaussian noise and generalization in a perceptron with binary weights. The averaged dynamics can be accurately modelled for both problems using a formalism which describes the dynamics of the GA using methods from statistical mechanics. The second problem is a simple example of a learning problem and by considering this problem we show how the accurate characterization of noise in the fitness evaluation may be relevant in machine learning. The training error (negative fitness) is the number of misclassified training examples in a batch and can be considered as a noisy version of the generalization error if an independent batch is used for each evaluation. The noise is due to the finite batch size and in the limit of large problem size and weak selection we show how the effect of this noise can be removed by increasing the population size. This allows the optimal batch size to be determined, which minimizes computation time as well as the total number of training examples required.
Resumo:
The dynamics of supervised learning in layered neural networks were studied in the regime where the size of the training set is proportional to the number of inputs. The evolution of macroscopic observables, including the two relevant performance measures can be predicted by using the dynamical replica theory. Three approximation schemes aimed at eliminating the need to solve a functional saddle-point equation at each time step have been derived.
Resumo:
The authors present a model of the multilevel effects of diversity on individual learning performance in work groups. For ethnically diverse work groups, the model predicts that group diversity elicits either positive or negative effects on individual learning performance, depending on whether a focal individual’s ethnic dissimilarity from other group members is high or low. By further considering the societal status of an individual’s ethnic origin within society (Anglo versus non-Anglo for our U.K. context), the authors hypothesize that the model’s predictions hold more strongly for non-Anglo group members than for Anglo group members. We test this model with data from 412 individuals working on a 24-week business simulation in 87 four- to seven-person groups with varying degrees of ethnic diversity. Two of the three hypotheses derived from the model received full support and one hypothesis received partial support. Implications for theory development, methods, and practice in applied group diversity research are discussed.
Resumo:
Gain insight into crucial British mental health approaches for LGB individuals. There is very little collaborative literature between LGB-affirmative psychologists and psychotherapists in the United States and the United Kingdom. British Lesbian, Gay, and Bisexual Psychologies: Theory, Research, and Practice may well be a crucial beginning step in building dialogue between these two countries on important LGB psychotherapy developments. Leading authorities comprehensively examine the latest studies and effective therapies for LGB individuals in the United Kingdom. Practitioners will discover an extensive survey of the most current developments to supplement their own work, while educators and students will find diverse expert perspectives on which to consider and broaden their own viewpoints. This unique book offers an informative introduction to British psychosocial perspectives on theory, research, and practice. British Lesbian, Gay, and Bisexual Psychologies provides a critical exploration of the recent history of LGB psychology and psychotherapy in the United Kingdom, focusing on key publications and outlining the current terrain. Other chapters are organized into two thematic sections. The first section explores theoretical frameworks in United Kingdom therapeutic practice, while the second section examines sexual minority identities and their needs for support and community. Topics in British Lesbian, Gay, and Bisexual Psychologies include: - similarities and differences between LGBT psychology and psychotherapy in the United States and United Kingdom - gay affirmative therapy (GAT) as a positive framework - existential-phenomenological approach to psychotherapy - core issues in the anxiety about whether or not to “come out” - object relations theory - exploring homo-negativity in the therapeutic process - aspects of psychotherapy that lesbians and gay men find helpful - research into how the mainstreaming of lesbian and gay culture has affected the lives of LGB individuals - study into LGB youth issues - difficulties of gay men with learning disabilities—with suggestions on how to offer the best psychological service - a study on gay athletes’ experiences of coming out in a heterosexist world British Lesbian, Gay, and Bisexual Psychologies takes a needed step toward sharing valuable psychosocial perspectives between countries. This useful, enlightening text is perfect for educators, students, psychologists, psychotherapists, and counselors working in the field of sexuality.
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Theory development on the relationship between strategic planning and organizational performance has focussed on largely discrete examinations of dependent and independent variables. While the literature has examined the impact of organizational learning on strategic planning, no holistic empirical approaches have been employed in order to fully explore the inter-play between these important constructs. This paper addresses the cited limitations in both the strategic planning and organizational performance literatures by creating profiles of organizational learning and strategic planning capacity using a configuration theory-based approach. The organizational learning orientation profiles (OLOPs) created of prospector, disseminator, interpretative and memory, contribute to theory development regarding the relationship of strategic planning and organizational learning. The theory developed provides insights that have not been previously reported.
Resumo:
This paper is about mothering, young learning disabled people, their sexualised and relationship lives and normalisation - not through the lens of the disabled person, but via a mothers perspective and theoretical discussion. As a mother who has a learning disabled daughter, a feminist and an academic, my own mothering experience, my PhD research and social theory are woven throughout this paper with the intention of opening up debate about sex, intimacy, normalisation, and how this impacts upon young learning disabled people. I suggest that the relationship between sex, reproduction, intimacy and intellectual impairment, and a project to decipher what it means to be human, in all its dirty glory are also part of the discourse that needs to be discussed experientially and theoretically. So much so that the messy world within which we all live can be variously and differently constructed.