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Conceptual Difficulties (conceptual + difficulty)
Selected AbstractsApplication of the New Keystone-Species Concept to Prairie Dogs: How Well Does It Work?CONSERVATION BIOLOGY, Issue 6 2000Natasha B. Kotliar This prompted Power et al. (1996) to refine the definition: keystone species have large effects on community structure or ecosystem function (i.e., high overall importance), and this effect should be large relative to abundance (i.e., high community importance). Using prairie dogs (Cynomys spp.) as an example, I review operational and conceptual difficulties encountered in applying this definition. As applied to prairie dogs, the implicit assumption that overall importance is a linear function of abundance is invalid. In addition, community importance is sensitive to abundance levels, the definition of community, and sampling scale. These problems arise largely from the equation for community importance, as used in conjunction with removal experiments at single abundance levels. I suggest that we shift from the current emphasis on the dualism between keystone and nonkeystone species and instead examine how overall and community importance vary (1) with abundance, (2) across spatial and temporal scales, and (3) under diverse ecological conditions. In addition, I propose that a third criterion be incorporated into the definition: keystone species perform roles not performed by other species or processes. Examination of how these factors vary among populations of keystone species should help identify the factors contributing to, or limiting, keystone-level functions, thereby increasing the usefulness of the keystone-species concept in ecology and conservation. Although the quantitative framework of Power et al. falls short of being fully operational, my conceptual guidelines may improve the usefulness of the keystone-species concept. Careful attention to the factors that limit keystone function will help avoid misplaced emphasis on keystone species at the expense of other species. Resumen: Se ha sugerido que el concepto de especie pilar no sea usado más en ecología y conservación, principalmente debido a que el concepto ha sido pobremente definido. Esto instigó a Power et al. (1996) a refinar la definición: las especies pilar tienen grandes efectos en la estructura de una comunidad o la función de un ecosistema (alta importancia en lo general), y este efecto debe ser grande en relación con la abundancia (alta importancia en la comunidad). Usando los perros de pradera (Cynomys spp) como ejemplo, revisé las dificultades operativas y conceptuales encontradas durante la aplicación de esta definición. Al aplicarse a perros de pradera, la suposición implícita de que la importancia en lo general es una función lineal de la abundancia es inválida. Además, la importancia en la comunidad es sensible a los niveles de abundancia, a la definición de comunidad y a la escala de muestreo. Estos problemas surgen, en gran medida, de la ecuación para la importancia en la comunidad, al ser usada conjuntamente con experimentos de remoción a un solo nivel de abundancia. Sugiero que el énfasis actual en la dualidad sobre especies pilares/no pilares cambie para examinar cómo varía la importancia en lo general y en la comunidad; (1) con la abundancia, (2) a lo largo de escalas espaciales y temporales, y (3) bajo diversas condiciones ecológicas. Además, propongo que sea incorporado un tercer criterio en la definición: las especies pilar llevan a cabo funciones no llevadas a cabo por otras especies o procesos. El análisis de cómo varían estos factores entre poblaciones de especies pilar ayudará a identificar los factores que contribuyen, o limitan las funciones a nivel pilar, incrementando con ello la utilidad del concepto de especie pilar en ecología y conservación. Aunque el marco de trabajo cuantitativo de Power et al. no llega a ser completamente operacional, mis guías conceptuales pueden mejorar la utilidad de este concepto. Una atención especial a los factores que limitan el funcionamiento pilar ayudaría a evitar un énfasis mal ubicado en especies pilar a costa de otras especies. [source] Contemporary issues and future directions for research into pathological gamblingADDICTION, Issue 8 2000Article first published online: 2 SEP 200 The recent healthy increase in research into all aspects of gambling is noted. The dominant theme accounting for most of this research is the mental disorder model of pathological gambling and measures that have been derived from this conceptualization. It is suggested that an alternative approach focusing on the construct of choice or subjective control over gambling may be a research direction that will ensure that progress is maintained. In this paper a context for the discussion is provided by first identifying briefly fundamental conceptual and methodological issues associated with the mental disorder model. In particular it is argued that the heterogeneity of the diagnosis of pathological gambling makes the research task of assessing truly independent variables extremely difficult. Subsequently an illustrative schema is presented that demonstrates both the potential advantages and some of the complexities associated with the dependent variable of self-control over gambling behaviour. The main advantages are argued to be (a) the focus of research is narrowed to one potential cause of harmful impacts rather than the great diversity of impacts themselves, (b) prospective studies of regular gamblers in real gambling venues may be a key source of insight into the development of pathological gambling and (c) it promotes the development of theoretical links with the mainstream of the discipline of psychology. Despite the conceptual difficulties that may be associated with the variable of self-control, it is suggested that these may be overcome because contemporary research into the addictive behaviours has demonstrated considerable success in the definition and measurement of control and related themes such as craving, restraint and temptation. [source] From massacre to the genocidal processINTERNATIONAL SOCIAL SCIENCE JOURNAL, Issue 174 2002Jacques Sémelin Since the time of Raphael Lemkin's work, genocide studies have been conducted primarily at the intersection of law and social science. As a result, the term ,genocide' has frequently been employed in a normative sense, leading to considerable conceptual difficulties and debate. How can such problems be overcome? This article comes down firmly in favour of moving away from a legal approach to genocide studies. It recommends the use of non-normative vocabulary based on the concept of ,massacre', this term being suggested as a reference lexical unit. It also puts forward the more general expression ,destruction process', whose most dramatic form is massacre. Massacre is not an act of actual ,madness' but the response to what the author calls ,delusional rationality'. In that respect, he distinguishes between two destruction strategies: one aimed at a group's subjugation and the other at its eradication. It is in the latter case that one can refer to a genocidal process. This article thus considers that genocide should not be defined as a static concept but viewed rather as a particular dynamic of civilian destruction, being the product of both its perpetrators' will and of favourable circumstances. [source] Staff in services for people with intellectual disabilities: the impact of stress on attributions of challenging behaviourJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 11 2005D. Rose Abstract Background There is a lack of a conceptual framework as to how stress and attribution variables interact and influence staff behaviour in response to challenging behaviour. To address this, a model is tested examining the impact of stress on attributions of challenging behaviour within Weiner's model of helping. Method A total of 107 staff working in community homes for people with intellectual disabilities completed a self-report questionnaire that measured stress, burnout, attributions, emotions, optimism and helping behaviour in response to challenging behaviour. Results Partial support was found for the role of attributions and emotions. However, although staff reported high stress levels and moderate burnout, this did not appear to relate to their reporting of thoughts and feelings regarding challenging behaviour predicted by Weiner's helping model. It was not possible to fully test the helping model, as the ,help' variable was not normally distributed. Conclusions There was little evidence to suggest that stress has a primary role in determining staff responses when examined within Weiner's model of helping. Limited support in general was offered for Weiner's helping model. Potential conceptual difficulties and clinical implications are explored and alternative models for future research are discussed. [source] Students' use of the energy model to account for changes in physical systemsJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 4 2008Nicos Papadouris Abstract The aim of this study is to explore the ways in which students, aged 11,14 years, account for certain changes in physical systems and the extent to which they draw on an energy model as a common framework for explaining changes observed in diverse systems. Data were combined from two sources: interviews with 20 individuals and an open-ended questionnaire that was administered to 240 students (121 upper elementary school students and 119 middle school students). We observed a wealth of approaches ranging from accounts of energy transfer and transformation to responses identifying specific objects or processes as the cause of changes. The findings also provide evidence that students do not seem to appreciate the transphenomenological and unifying nature of energy. Students' thinking was influenced by various conceptual difficulties that are compounded by traditional science teaching; for instance, students tended to confuse energy with force or electric current. In addition, the comparison between the responses from middle school students and those of elementary school students demonstrates that science teaching and maturation appeared to have a negligible influence on whether students had constructed a coherent energy model, which they could use consistently to account for changes in certain physical systems. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 45: 444,469, 2008 [source] The Politics of Perception: Use and Abuse of Transparency International's Approach to Measuring CorruptionPOLITICAL STUDIES, Issue 4 2009Staffan Andersson The annual Corruption Perceptions Index (CPI), published by Transparency International (TI), has had a pivotal role in focusing attention on corruption. Despite recent critiques of the CPI, it remains highly influential on research into the causes of corruption and is also extensively used to galvanise support for measures to fight corruption. In this article we explore the CPI in more depth in order to highlight how the index has been used for political ends which may not always turn out to be supportive of anti-corruption efforts. The argument is developed in four sections: in the first, we focus on Transparency International's definition of corruption, highlighting some conceptual difficulties with the approach adopted and its relationship to the promotion of ,good governance' as the principal means of combating corruption. In the second section, we outline some methodological difficulties in the design of the Corruption Perceptions Index. Although the CPI has been much criticised, we demonstrate in the third section that the index continues to exercise great influence both in academic research and in the politics of anti-corruption efforts, particularly as exercised by Transparency International itself. In the final section we argue that the CPI contributes to the risk of creating a ,corruption trap' in countries where corruption is deeply embedded, as development aid is increasingly made conditional on the implementation of reforms which are impossible to achieve without that aid. [source] Implications of Applying a Private Sector Based Reporting Model to Not-for-Profit Entities: The Treatment of Charitable Distributions by Charities in New ZealandAUSTRALIAN ACCOUNTING REVIEW, Issue 1 2009Chris Van Staden In this paper, we investigate the practical and conceptual difficulties caused by applying a private sector based reporting model to the not-for-profit sector. We deal specifically with reporting on charitable distributions by charities in New Zealand. We find a majority of the entities report charitable distributions in the Statement of Financial Performance (as expenses). This approach is conceptually justifiable, complies with international best practice, and is in line with the accountability argument made in this paper. While the number reduced between 2003 and 2007, a significant minority of the entities report charitable distributions in the Statement of Movements in Equity (and therefore report higher surpluses). These two approaches lead to very different results, yet both are apparently seen as acceptable by the entities and their auditors. While this raises questions as to the understandability and comparability of the financial reporting by these entities, it also raises questions about the suitability of the for-profit sector reporting requirements for the not-for-profit sector. [source] | |||||||||||||