896 resultados para Positive-p Representation
Resumo:
Recentiy a neuropsychological model of learning has been proposed Qackson, 2002) which argues that Responsibility provides a cognitive re-expression of Impulsivit)' in the prediction of functional and dysfunctional behaviour. Jackson argues that primitive, instinctive impulses lead to antisocial behaviours and socio-cognitive regulators such as Responsibility leads to the re-expression of Impulsivity in terms of pro-social behaviours. Study 1 tests and supports the measurement properties of the assessment methodology associated with the model. Study 2 provides evidence in favour of the instinctive basis of Impulsivity and the conscious basis of Responsibility, which reinforces the underlying neuropsychological basis of the model. Study 3 uses structural equation modelling to determine if Responsibility mediates Impulsivity in the prediction of a latent variable representing work performance, work commitment and team performance, but does not mediate Impulsivit}' in the prediction of a latent variable representing sexual proclivity, workplace deviancy, gambling and beer consumption. Results provide strong support for Jackson's model and suggest that Impulsivity and Responsibility are fundamental to both functional and dysfunctional learning
Resumo:
Recovering position from sensor information is an important problem in mobile robotics, known as localisation. Localisation requires a map or some other description of the environment to provide the robot with a context to interpret sensor data. The mobile robot system under discussion is using an artificial neural representation of position. Building a geometrical map of the environment with a single camera and artificial neural networks is difficult. Instead it would be simpler to learn position as a function of the visual input. Usually when learning images, an intermediate representation is employed. An appropriate starting point for biologically plausible image representation is the complex cells of the visual cortex, which have invariance properties that appear useful for localisation. The effectiveness for localisation of two different complex cell models are evaluated. Finally the ability of a simple neural network with single shot learning to recognise these representations and localise a robot is examined.
Resumo:
Neural networks can be regarded as statistical models, and can be analysed in a Bayesian framework. Generalisation is measured by the performance on independent test data drawn from the same distribution as the training data. Such performance can be quantified by the posterior average of the information divergence between the true and the model distributions. Averaging over the Bayesian posterior guarantees internal coherence; Using information divergence guarantees invariance with respect to representation. The theory generalises the least mean squares theory for linear Gaussian models to general problems of statistical estimation. The main results are: (1)~the ideal optimal estimate is always given by average over the posterior; (2)~the optimal estimate within a computational model is given by the projection of the ideal estimate to the model. This incidentally shows some currently popular methods dealing with hyperpriors are in general unnecessary and misleading. The extension of information divergence to positive normalisable measures reveals a remarkable relation between the dlt dual affine geometry of statistical manifolds and the geometry of the dual pair of Banach spaces Ld and Ldd. It therefore offers conceptual simplification to information geometry. The general conclusion on the issue of evaluating neural network learning rules and other statistical inference methods is that such evaluations are only meaningful under three assumptions: The prior P(p), describing the environment of all the problems; the divergence Dd, specifying the requirement of the task; and the model Q, specifying available computing resources.
Resumo:
A content analysis examined the way majorities and minorities are represented in the British press. An analysis of the headlines of five British newspapers, over a period of five years, revealed that the words ‘majority’ and ‘minority’ appeared 658 times. Majority headlines were most frequent (66% ), more likely to emphasize the numerical size of the majority, to link majority status with political groups, to be described with positive evaluations, and to cover political issues. By contrast, minority headlines were less frequent (34%), more likely to link minority status with ethnic groups and to other social issues, and less likely to be described with positive evaluations. The implications of examining how real-life majorities and minorities are represented for our understanding of experimental research are discussed.