1000 resultados para Situation Representation
Resumo:
The literature has difficulty explaining why the number of parties in majoritarian electoral systems often exceeds the two-party predictions associated with Duverger’s Law. To understand why this is the case, I examine several party systems in Western Europe before the adoption of proportional representation. Drawing from the social cleavage approach, I argue that the emergence of multiparty systems was because of the development of the class cleavage, which provided a base of voters sizeable enough to support third parties. However, in countries where the class cleavage became the largest cleavage, the class divide displaced other cleavages and the number of parties began to converge on two. The results show that the effect of the class cleavage was nonlinear, producing the greatest party system fragmentation in countries where class cleavages were present – but not dominant – and smaller in countries where class cleavages were either dominant or non-existent.
Resumo:
Belief revision performs belief change on an agent’s beliefs when new evidence (either of the form of a propositional formula or of the form of a total pre-order on a set of interpretations) is received. Jeffrey’s rule is commonly used for revising probabilistic epistemic states when new information is probabilistically uncertain. In this paper, we propose a general epistemic revision framework where new evidence is of the form of a partial epistemic state. Our framework extends Jeffrey’s rule with uncertain inputs and covers well-known existing frameworks such as ordinal conditional function (OCF) or possibility theory. We then define a set of postulates that such revision operators shall satisfy and establish representation theorems to characterize those postulates. We show that these postulates reveal common characteristics of various existing revision strategies and are satisfied by OCF conditionalization, Jeffrey’s rule of conditioning and possibility conditionalization. Furthermore, when reducing to the belief revision situation, our postulates can induce Darwiche and Pearl’s postulates C1 and C2.
Resumo:
This article focuses on the issue of Northern Ireland's representation at Westminster. It investigates the political context of the decision to increase Northern Ireland's representation in the house of commons at Westminster from 12 members to 17 in 1978-9. Exploring this episode in more detail, it is argued, provides a more informed overall understanding of the history of devolution in the UK and of the way issues concerning Northern Ireland often overlapped with questions of constitutional change in Scotland and Wales. The article also throws light on the matter of Northern Ireland MPs and their voting rights at Westminster during Northern Ireland's experience of devolution prior to 1972.
Resumo:
The predominant fear in capital markets is that of a price spike. Commodity markets differ in that there is a fear of both upward and down jumps, this results in implied volatility curves displaying distinct shapes when compared to equity markets. The use of a novel functional data analysis (FDA) approach, provides a framework to produce and interpret functional objects that characterise the underlying dynamics of oil future options. We use the FDA framework to examine implied volatility, jump risk, and pricing dynamics within crude oil markets. Examining a WTI crude oil sample for the 2007–2013 period, which includes the global financial crisis and the Arab Spring, strong evidence is found of converse jump dynamics during periods of demand and supply side weakness. This is used as a basis for an FDA-derived Merton (1976) jump diffusion optimised delta hedging strategy, which exhibits superior portfolio management results over traditional methods.
Resumo:
Funded by the Economic and Social Research Council this partnership project between the Childhood, Transition and Social Justice Initiative at Queen’s University and Include Youth focuses on the negative stereotyping of children and young people and the role and responsibilities of the media in the creation and transmission of negative images. Engaging with children, young people, organisations working with children and young people and media representatives, the project uses research evidence to explore negative media representation and its consequences for children’s rights, public reaction and policy initiatives in Northern Ireland. This report represents a summary of the findings of engagement with 141 children and young people. It outlines how they feel they are presented by the media and the impacts of this. It concludes by noting ways forward in challenging negative portrayals.
Resumo:
A debate on the effect of environmental practices on performance has been taking place in the academic literature over the last two decades. In recent years this has involved researchers looking beyond the direct relationship between practices and performance to consider other potential contributing factors. This paper considers the extent to which environmental proactivity influences the practices that firms adopt and the associated performance outcomes. Data were collected from sample of UK food manufacturers and analysed using multiple regression analysis. Findings suggest that proactivity is an important antecedent to practices but these practices may not lead to improvements beyond environmental performance.
Resumo:
Situation calculus has been applied widely in arti?cial intelligence to model and reason about actions and changes in dynamic systems. Since actions carried out by agents will cause constant changes of the agents’ beliefs, how to manage
these changes is a very important issue. Shapiro et al. [22] is one of the studies that considered this issue. However, in this framework, the problem of noisy sensing, which often presents in real-world applications, is not considered. As a
consequence, noisy sensing actions in this framework will lead to an agent facing inconsistent situation and subsequently the agent cannot proceed further. In this paper, we investigate how noisy sensing actions can be handled in iterated
belief change within the situation calculus formalism. We extend the framework proposed in [22] with the capability of managing noisy sensings. We demonstrate that an agent can still detect the actual situation when the ratio of noisy sensing actions vs. accurate sensing actions is limited. We prove that our framework subsumes the iterated belief change strategy in [22] when all sensing actions are accurate. Furthermore, we prove that our framework can adequately handle belief introspection, mistaken beliefs, belief revision and belief update even with noisy sensing, as done in [22] with accurate sensing actions only.
Resumo:
This article examines the nature of gender politics in Northern Ireland since the 1998 Good Friday/Belfast Agreement. Taking gender justice as a normative democratic framework, the article argues that despite the promise of women's equal participation in public and political life written into the Agreement, parties have delivered varied responses to integrating women, women's interests and perspectives into politics and policy platforms. This contrasts with general patterns supporting women's increased participation in social and political life. The article discusses women's descriptive and substantive representation through electoral outcomes and party manifestos, using the demands of successive women's manifestos as a benchmark. It concludes that while parties have given less recognition and inclusion to women than one might have expected in a new political context, the push for democratic accountability will ensure that gender politics will continue to have a place on the political agenda for some time to come.
Resumo:
this article discusses the three main strategies employed across the globe to raise the levels of women's political representation