An illustration of variable precision rough set theory : The gender classification of the European barn swallow (Hirundo rustica)

This paper introduces a new technique in the investigation of object classification and illustrates the potential use of this technique for the analysis of a range of biological data, using avian morphometric data as an example. The nascent variable precision rough sets (VPRS) model is introduced and compared with the decision tree method ID3 (through a ‘leave n out’ approach), using the same dataset of morphometric measures of European barn swallows (Hirundo rustica) and assessing the accuracy of gender classification based on these measures. The results demonstrate that the VPRS model, allied with the use of a modern method of discretization of data, is comparable with the more traditional non-parametric ID3 decision tree method. We show that, particularly in small samples, the VPRS model can improve classification and to a lesser extent prediction aspects over ID3. Furthermore, through the ‘leave n out’ approach, some indication can be produced of the relative importance of the different morphometric measures used in this problem. In this case we suggest that VPRS has advantages over ID3, as it intelligently uses more of the morphometric data available for the data classification, whilst placing less emphasis on variables with low reliability. In biological terms, the results suggest that the gender of swallows can be determined with reasonable accuracy from morphometric data and highlight the most important variables in this process. We suggest that both analysis techniques are potentially useful for the analysis of a range of different types of biological datasets, and that VPRS in particular has potential for application to a range of biological circumstances.

An email classification model based on rough set theory

The communication via email is one of the most popular services of the Internet. Emails have brought us great convenience in our daily work and life. However, unsolicited messages or spam, flood our email boxes, which results in bandwidth, time and money wasting. To this end, this paper presents a rough set based model to classify emails into three categories - spam, no-spam and suspicious, rather than two classes (spam and non-spam) in most currently used approaches. By comparing with popular classification methods like Naive Bayes classification, the error ratio that a non-spam is discriminated to spam can be reduced using our proposed model.

Interrogating conceptions of “vulnerable youth” in theory, policy and practice

Young people who are considered ‘vulnerable’ or ‘at risk’ are a particular target of various policies, schemes and interventions. But what does vulnerability mean? Interrogating Conceptions of “Vulnerable Youth” explores this question in relation to various policy fields that are relevant to young people, as well for how this plays out in practice and how it is experienced by young people themselves. What makes this book unique is that most authors had the opportunity to jointly explore these issues during a two-day workshop, and their chapters are informed by their cross-agency and cross-discipline discussions, making for a nuanced and thoughtful set of contributions. This collection is highly recommended for researchers and research students in the social sciences, as well as professional staff working in youth policy and youth services, in government departments and in NGOs. “Those who are most vulnerable should receive our greatest moral attention. However, the translation of generalised moral principles into effective policy and programs has never been easy. Political interests have invariably intervened, leading to complex debates about how vulnerability should be defined, classified, measured and represented. In recent years, these debates have become further complicated, as nation-states around the world have preached austerity. This timely book suggests that the responsibility for protecting the vulnerable cannot be left to individuals, but demands collective action, through institutions such as education, health and welfare. It examines some of the ways in which public policies and programs represent those who are vulnerable, involving a range of assumptions about the social, economic and political conditions that produce their vulnerabilities.” From the Foreword by Professor Fazal Rizvi

Flow analysis based on a pulsed flow of solution: theory, instrumentation and applications

The increased demands placed on solution propulsion by programmed flow systems, such as sequential injection analysis, lab-on-value technology, bead injection and multi-commutation, has highlighted the inability of many conventional pumps to generate a smooth, consistent flow. A number of researchers have examined ways to overcome the inadvertent, uncontrolled pulsation caused by the mechanical action of peristaltic pumps. In contrast, we have developed instruments that exploit the characteristics of a reproducible pulsed flow of solution. In this paper, we discuss our instrumental approaches and some applications that have benefited from the use of a reproducible pulsed flow rather than the traditional linear flow approach. To place our approach in the context of the continuously developing field of flow analysis, an overview of other programmed flow systems is also presented.

Geometry and combinatorics of the cutting angle method

Lower approximation of Lipschitz functions plays an important role in deterministic global optimization. This article examines in detail the lower piecewise linear approximation which arises in the cutting angle method. All its local minima can be explicitly enumerated, and a special data structure was designed to process them very efficiently, improving previous results by several orders of magnitude. Further, some geometrical properties of the lower approximation have been studied, and regions on which this function is linear have been identified explicitly. Connection to a special distance function and Voronoi diagrams was established. An application of these results is a black-box multivariate random number generator, based on acceptance-rejection approach.

Reinforcement sensitivity theory (RST) and body change behaviour in males

According to the unrevised Reinforcement Sensitivity Theory two motivational systems shape personality: a behavioural approach system (BAS) that determines sensitivity to rewards, and a behavioural inhibition system (BIS) that determines sensitivity to punishments. The role of reinforcement sensitivity in body change behaviour in males was explored with a non-clinical sample of 120 men aged 18–40 years. Self-reported symptoms of unhealthy weight loss (weight preoccupation, fasting, bingeing/purging) and body development (muscle/size preoccupation, obligatory exercise, use of chemical supplements) were regressed on measures of BAS and BIS sensitivity. Significant relationships were observed between BAS sensitivity and body development, and between BIS sensitivity and weight loss. These relationships were mediated by internalization of the athletic/muscular ideal, body comparisons, the importance of achieving one’s ideal or ‘best possible’ body (in the case of BAS but not BIS), and body dissatisfaction (in the case of BIS but not BAS). These results support the proposition that body development in males is influenced by sensitivity to rewards associated with achieving a certain body shape, and that weight loss is influenced by sensitivity to punishments associated with possessing an unsatisfactory body shape.

Museum pricing : challenges to theory development and practice

The museum sector has undergone considerable change in the last few decades, which has been a result of both internal and external forces. The topic of pricing in museums, however, has attracted little interest from researchers in the field despite the sector's need to understand it better. This study aimed to address this gap in knowledge. Results of a comprehensive literature review on pricing highlight that the topic of pricing in museums is problematic, as a range of issues, social, political and often value-laden, must be considered before pricing decisions can be made. The study highlights that there is diversity in the sector with regard to pricing, but that museums generally adopt a unilateral approach to pricing. Researchers in entrepreneurial marketing have noted that conventional pricing theory is being turned on its head and they argue that deciding what prices to charge represents one of the more entrepreneurial strategies for organisations. This study indicates that, within the context of museums, marketers are failing to recognise and capitalise on such pricing opportunities. Approaches to setting multiple museum pricing strategies, depending on the market context, are proposed in this paper. In this way, knowledge of museum pricing can optimise the organisational outcomes of museums while continuing to meet their social responsibilities.

A creative twist: management theory, creativity and the arts

For many theorists and practitioners in the area of organizational theory, HRM, marketing and other domains of organization studies, organizational creativity is something to be distilled and managed as an element of organizational performance. The article argues, however, that this process of appropriation from the creative arts is subject to a number of problematic transitions. The article's starting point is the notion of creativity itself. Within the creative arts, the question of what constitutes creativity and its relationship to artistic practice is subject to considerable debate. This debate centers on the question of whether creativity represents an essentialist and inexplicable (even spiritual) component of artistic practice or whether creativity is a trait of work and cannot be attributed as a unique aspect of art. The mantra of creativity provides nothing more than a means to control individuals and provide them with a false hope that contributing to the success of business will provide a means to self fulfillment.