What happens to precocious readers’ performance by the age of 11 years?

This paper reports on the progress made by a group of fourteen 11-year-old children who had been originally identified as being precocious readers before they started primary school at the age of 5-years. The data enable comparisons to be made with the performance of the children when they were younger so that a six year longitudinal analysis can be made. The children who began school as precocious readers continued to make progress in reading accuracy, rate and comprehension, thereby maintaining their superior performance relative to a comparison group. However, their progress appeared to follow the same developmental trajectory as that of the comparison group. Measures of phonological awareness showed that there are long term, stable individual differences which correlated with all measures of reading. The children who were reading precociously early showed significantly higher levels of phonological awareness than the comparison children. In addition, they showed the same levels of performance on this task as a further group of high achieving young adults. A positive effect of being able to read at precociously early age was identified in the significantly higher levels of receptive vocabulary found amongst the these children. The analyses indicated that rises in receptive vocabulary resulted from reading performance rather than the other way round

Verbal short‐term memory performance in pupils with Down Syndrome

Research has shown that verbal short‐term memory span is shorter in individuals with Down syndrome than in typically developing individuals of equivalent mental age, but little attention has been given to variations within or across groups. Differences in the environment and in particular educational experiences may play a part in the relative ease or difficulty with which children remember verbal material. This article explores the performance of 26 Egyptian pupils with Down syndrome and 26 Egyptian typically developing children on two verbal short‐term memory tests: digit recall and non‐word repetition tasks. The findings of the study revealed that typically developing children showed superior performance on these tasks to that of pupils with Down syndrome, whose performance was both lower and revealed a narrower range of attainment. Comparisons with the performance of children with Down syndrome in this study suggested that not only did the children with Down syndrome perform more poorly than the typically developing children, their profile also appeared worse than the results of studies of children with a similar mental age with Down syndrome carried out in western countries. The results from this study suggested that, while deficits in verbal short‐term memory in Down syndrome may well be universal, it is important to recognise that performances may vary as a consequence of culture and educational experiences. The significance of these findings is explored with reference to approaches to education and how these are conceptualised in relation to children with disabilities.

Rethinking the literature on the performance of Chinese multinational enterprises

We synthesize the literature on Chinese multinational enterprises (MNEs) and find that much of the prior research is based on as few as a dozen case studies of Chinese firms. They are so case-specific that it has led to a misplaced call for new theories to explain Chinese firms’ internationalization. In an attempt to better relate theory with empirical evidence, we examine the largest 500 Chinese manufacturing firms. We aim to find out the number of Chinese manufacturing firms to be true MNEs by definition, and to examine their financial performance relative to global peers using the financial benchmarking method. We develop our theoretical perspectives from new internalization theory. We find that there are only 49 Chinese manufacturing firms to be true MNEs, whereas the rest is purely domestic firms. Their performance is poor relative to global peers. Chinese MNEs have home country bound firm-specific advantages (FSAs), which are built upon home country-specific advantages (home CSAs). They have not yet developed advanced management capabilities through recombination with host CSAs. Essentially, they acquire foreign firms to increase their sales in domestic market, but they fail to be competitive internationally and to achieve superior performance in overseas operations. Our findings have important strategic implications for managers, public policy makers, and academic research.

Biologically motivated model for object detection and identification in real-world scenes

The classical computer vision methods can only weakly emulate some of the multi-level parallelisms in signal processing and information sharing that takes place in different parts of the primates’ visual system thus enabling it to accomplish many diverse functions of visual perception. One of the main functions of the primates’ vision is to detect and recognise objects in natural scenes despite all the linear and non-linear variations of the objects and their environment. The superior performance of the primates’ visual system compared to what machine vision systems have been able to achieve to date, motivates scientists and researchers to further explore this area in pursuit of more efficient vision systems inspired by natural models. In this paper building blocks for a hierarchical efficient object recognition model are proposed. Incorporating the attention-based processing would lead to a system that will process the visual data in a non-linear way focusing only on the regions of interest and hence reducing the time to achieve real-time performance. Further, it is suggested to modify the visual cortex model for recognizing objects by adding non-linearities in the ventral path consistent with earlier discoveries as reported by researchers in the neuro-physiology of vision.

Time-varying coefficients in the almost ideal demand system: An empirical appraisal

This paper provides a generalisation of the structural time series version of the Almost Ideal Demand System (AIDS) that allows for time-varying coefficients (TVC/AIDS) in the presence of cross-equation constraints. An empirical appraisal of the TVC/AIDS is made using a dynamic AIDS with trending intercept as the baseline model with a data set from the Italian Household Budget Survey (1986-2001). The assessment is based on four criteria: adherence to theoretical constraints, statistical diagnostics on residuals, forecasting performance and economic meaningfulness. No clear evidence is found for superior performance of the TVC/AIDS, apart from improved short-term forecasts.

Texture segmentation in Williams syndrome

Williams syndrome (WS) is a developmental disorder in which visuo-spatial cognition is poor relative to verbal ability. At the level of visuo-spatial perception, individuals with WS can perceive both the local and global aspects of an image. However, the manner in which local elements are integrated into a global whole is atypical, with relative strengths in integration by luminance, closure, and alignment compared to shape, orientation and proximity. The present study investigated the manner in which global images are segmented into local parts. Segmentation by seven gestalt principles was investigated: proximity, shape, luminance, orientation, closure, size (and alignment: Experiment I only). Participants were presented with uniform texture squares and asked to detect the presence of a discrepant patch (Experiment 1) or to identify the form of a discrepant patch as a capital E or H (Experiment 2). In Experiment 1, the pattern and level of performance of the WS group did not differ from that of typically developing controls, and was commensurate with the general level of non-verbal ability observed in WS. These results were replicated in Experiment 2, with the exception of segmentation by proximity, where individuals with WS demonstrated superior performance relative to the remaining segmentation types. Overall, the results suggest that, despite some atypical aspects of visuo-spatial perception in WS, the ability to segment a global form into parts is broadly typical in this population. In turn, this informs predictions of brain function in WS, particularly areas V1 and V4. (c) 2006 Elsevier Ltd. All rights reserved.

The British ‘failure’ that never was? The Anglo-American ‘productivity gap’ in large-scale interwar retailing—evidence from the department store sector

Interwar British retailing has been characterized as having lower productivity, less developed managerial hierarchies and methods, and weaker scale economies than its US counterpart. This article examines comparative productivity for one major segment of large-scale retailing in both countries—the department store sector. Drawing on exceptionally detailed contemporary survey data, we show that British department stores in fact achieved superior performance in terms of operating costs, margins, profits, and stock-turn. While smaller British stores had lower labour productivity than US stores of equivalent size, TFP was generally higher for British stores, which also enjoyed stronger scale economies. We also examine the reasons behind Britain's surprisingly strong relative performance, using surviving original returns from the British surveys. Contrary to arguments that British retailers faced major barriers to the development of large-scale enterprises, that could reap economies of scale and scope and invest in machinery and marketing to support the growth of their primary sales functions, we find that British department stores enthusiastically embraced the retail ‘managerial revolution’—and reaped substantial benefits from this investment.

A robust controller design method for feedback substitution schemes using genetic algorithms

Controllers for feedback substitution schemes demonstrate a trade-off between noise power gain and normalized response time. Using as an example the design of a controller for a radiometric transduction process subjected to arbitrary noise power gain and robustness constraints, a Pareto-front of optimal controller solutions fulfilling a range of time-domain design objectives can be derived. In this work, we consider designs using a loop shaping design procedure (LSDP). The approach uses linear matrix inequalities to specify a range of objectives and a genetic algorithm (GA) to perform a multi-objective optimization for the controller weights (MOGA). A clonal selection algorithm is used to further provide a directed search of the GA towards the Pareto front. We demonstrate that with the proposed methodology, it is possible to design higher order controllers with superior performance in terms of response time, noise power gain and robustness.

Is prospective memory enhanced by cue-action semantic relatedness and enactment at encoding?

Benefits and costs on prospective memory performance, of enactment at encoding and a semantic association between a cue-action word pair, were investigated in two experiments. Findings revealed superior performance for both younger and older adults following enactment, in contrast to verbal encoding, and when cue-action semantic relatedness was high. Although younger adults outperformed older adults, age did not moderate benefits of cue-action relatedness or enactment. Findings from a second experiment revealed that the inclusion of an instruction to perform a prospective memory task led to increments in response latency to items from the ongoing activity in which that task was embedded, relative to latencies when the ongoing task only was performed. However, this task interference ‘cost’ did not differ as a function of either cue-action relatedness or enactment. We argue that the high number of cue-action pairs employed here influenced meta-cognitive consciousness, hence determining attention allocation, in all experimental conditions.

Can profitable trading strategies be derived from investment best-sellers?

A glance along the finance shelves at any bookshop reveals a large number of books that seek to show readers how to ‘make a million’ or ‘beat the market’ with allegedly highly profitable equity trading strategies. This paper investigates whether useful trading strategies can be derived from popular books of investment strategy, with What Works on Wall Street by James P. O'Shaughnessy used as an example. Specifically, we test whether this strategy would have produced a similarly spectacular performance in the UK context as was demonstrated by the author for the US market. As part of our investigation, we highlight a general methodology for determining whether the observed superior performance of a trading rule could be attributed in part or in entirety to data mining. Overall, we find that the O'Shaughnessy rule performs reasonably well in the UK equity market, yielding higher returns than the FTSE All-Share Index, but lower returns than an equally weighted benchmark

Type-1 error inflation in the traditional by-participant analysis to metamemory accuracy: a generalized mixed-effects model perspective

In order to examine metacognitive accuracy (i.e., the relationship between metacognitive judgment and memory performance), researchers often rely on by-participant analysis, where metacognitive accuracy (e.g., resolution, as measured by the gamma coefficient or signal detection measures) is computed for each participant and the computed values are entered into group-level statistical tests such as the t-test. In the current work, we argue that the by-participant analysis, regardless of the accuracy measurements used, would produce a substantial inflation of Type-1 error rates, when a random item effect is present. A mixed-effects model is proposed as a way to effectively address the issue, and our simulation studies examining Type-1 error rates indeed showed superior performance of mixed-effects model analysis as compared to the conventional by-participant analysis. We also present real data applications to illustrate further strengths of mixed-effects model analysis. Our findings imply that caution is needed when using the by-participant analysis, and recommend the mixed-effects model analysis.

Low rank representation on Riemannian manifold of symmetric positive definite matrices

Sparse coding aims to find a more compact representation based on a set of dictionary atoms. A well-known technique looking at 2D sparsity is the low rank representation (LRR). However, in many computer vision applications, data often originate from a manifold, which is equipped with some Riemannian geometry. In this case, the existing LRR becomes inappropriate for modeling and incorporating the intrinsic geometry of the manifold that is potentially important and critical to applications. In this paper, we generalize the LRR over the Euclidean space to the LRR model over a specific Rimannian manifold—the manifold of symmetric positive matrices (SPD). Experiments on several computer vision datasets showcase its noise robustness and superior performance on classification and segmentation compared with state-of-the-art approaches.

In situ gelling systems based on Pluronic F127/Pluronic F68 formulations for ocular drug delivery

This study evaluated the use of Pluronic F127 and Pluronic F68 as excipients for formulating in situ gelling systems for ocular drug delivery. Thermal transitions have been studied in aqueous solutions of Pluronic F127, Pluronic F68 as well as their binary mixtures using differential scanning calorimetry, rheological measurements, and dynamic light scattering. It was established that the formation of transparent gels at physiologically relevant temperatures is observed only in the case of 20 wt % of Pluronic F127. The addition of Pluronic F68 to Pluronic F127 solutions increases the gelation temperature of binary formulation to above physiological range of temperatures. The biocompatibility evaluation of these formulations using slug mucosa irritation assay and bovine corneal erosion studies revealed that these polymers and their combinations do not cause significant irritation. In vitro drug retention study on glass surfaces and freshly excised bovine cornea showed superior performance of 20 wt % Pluronic F127 compared to other formulations. In addition, in vivo studies in rabbits demonstrated better retention performance of 20 wt % Pluronic F127 compared to Pluronic F68. These results confirmed that 20 wt % Pluronic F127 offers an attractive ocular formulation that can form a transparent gel in situ under physiological conditions with minimal irritation.

Integrating woodland with pig production in the United Kingdom: an investigation of potential performance and interactions

Although silvopastoral systems involving pigs were once widespread in Britain, the practice has largely died out. However, recent changes in pig production techniques, consumer demands and the economic climate within which farmers operate, have led to renewed interest in both traditional and novel tree-pig systems. This paper describes a financial spreadsheet model (MAST) that was developed to: provide a means of determining financial performance of integrating finishing pigs with natural woodland; identify the likely importance of different as yet largely unresearched animal-tree interactions; and, determine which interactions warrant attention in research and management. Preliminary analysis suggests that the financial performance of this agroforestry enterprise could be superior to that of a pasture-based enterprise. The most important factors in determining incremental performance are identified as sales premia for ‘forest-reared’ pork, changes to feed conversion ratios arising from the provision of a heterogeneous microclimate, and the availability of cheaper land rents.

Integrating natural woodland with pig production in the United Kingdom: an investigation of potential performance and interactions

Although silvopastoral systems involving pigs were once widespread in Britain, the practice has largely died out. However, recent changes in pig production techniques, consumer demands and the economic climate within which farmers operate, have led to renewed interest in both traditional and novel tree-pig systems. This paper describes a financial spreadsheet model ( MAST) that was developed to: provide a means of determining financial performance of integrating finishing pigs with natural woodland; identify the likely importance of different as yet largely unresearched animal-tree interactions; and, determine which interactions warrant attention in research and management. Preliminary analysis suggests that the financial performance of this agroforestry enterprise could be superior to that of a pasture-based enterprise. The most important factors in determining incremental performance are identified as sales premia for 'forest-reared' pork, changes to feed conversion ratios arising from the provision of a heterogeneous microclimate, and the availability of cheaper land rents.