• Title/Summary/Keyword: Evidence Theory

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Representing Fuzzy, Uncertain Evidences and Confidence Propagation for Rule-Based System

  • Zhang, Tailing
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1254-1263
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    • 1993
  • Representing knowledge uncertainty , aggregating evidence confidences , and propagation uncertainties are three key elements that effect the ability of a rule-based expert system to represent domains with uncertainty . Fuzzy set theory provide a good mathematical tool for representing the vagueness associated with a variable when , as the condition of a rule , it only partially corresponds to the input data. However, the aggregation of ANDed and Ored confidences is not as simple as the intersection and union operators defined for fuzzy set membership. There is, in fact, a certain degree of compensation that occurs when an expert aggregates confidences associated with compound evidence . Further, expert often consider individual evidences to be varying importance , or weight , in their support for a conclusion. This paper presents a flexible approach for evaluating evidence and conclusion confidences. Evidences may be represented as fuzzy or nonfuzzy variables with as associat d degree of certainty . different weight can also be associated degree of certainty. Different weights can also be assigned to the individual condition in determining the confidence of compound evidence . Conclusion confidence is calculated using a modified approach combining the evidence confidence and a rule strength. The techniques developed offer a flexible framework for representing knowledge and propagating uncertainties. This framework has the potention to reflect human aggregation of uncertain information more accurately than simple minimum and maximum operator do.

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RISK-INFORMED REGULATION: HANDLING UNCERTAINTY FOR A RATIONAL MANAGEMENT OF SAFETY

  • Zio, Enrico
    • Nuclear Engineering and Technology
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    • v.40 no.5
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    • pp.327-348
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    • 2008
  • A risk-informed regulatory approach implies that risk insights be used as supplement of deterministic information for safety decision-making purposes. In this view, the use of risk assessment techniques is expected to lead to improved safety and a more rational allocation of the limited resources available. On the other hand, it is recognized that uncertainties affect both the deterministic safety analyses and the risk assessments. In order for the risk-informed decision making process to be effective, the adequate representation and treatment of such uncertainties is mandatory. In this paper, the risk-informed regulatory framework is considered under the focus of the uncertainty issue. Traditionally, probability theory has provided the language and mathematics for the representation and treatment of uncertainty. More recently, other mathematical structures have been introduced. In particular, the Dempster-Shafer theory of evidence is here illustrated as a generalized framework encompassing probability theory and possibility theory. The special case of probability theory is only addressed as term of comparison, given that it is a well known subject. On the other hand, the special case of possibility theory is amply illustrated. An example of the combination of probability and possibility for treating the uncertainty in the parameters of an event tree is illustrated.

Bayesian concept of evidence (베이즈주의에서의 증거 개념)

  • Lee, Yeong-Eui
    • Korean Journal of Logic
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    • v.8 no.2
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    • pp.33-58
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    • 2005
  • The old evidence problem raises a profound problem to Bayesian theory of confirmation that evidence known prior to a hypothesis explaining it cannot give any empirical support to the hypothesis. The old evidence problem has resisted to a lot of trials to solve it. The purpose of the paper is to solve the old evidence problem by showing that the problem originated from a serious misunderstanding about the Bayesian concept of confirmation. First, I shall make a brief analysis of the problem, and examine critically two typical Bayesian strategies to solve it. Second, I shah point out a misunderstanding commonly found among Bayesian discussions about the old evidence problem, the ignorance of the asymmetry of confirmation in the context of explanation and prediction. Lastly, 1 shall suggest two different concepts of confirmations by using the asymmetry and argue that the concept of confirmation presupposed in the old evidence problem is not a genuine Bayesian concept of confirmation.

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Sixth Graders' Inquiry Understanding for Scientific Evidence and Explanation (과학적 증거와 설명에 대한 초등학교 6학년 학생의 이해)

  • Jeong, Hei-Sawn;Oh, Eun-A
    • Journal of The Korean Association For Science Education
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    • v.23 no.6
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    • pp.634-649
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    • 2003
  • The aim of this paper was to diagnose Korean sixth graders' understanding for scientific evidence and explanation. The instrument constructed by Jeong, Songer, and Lee (2002) was used to assess students' understanding for priority of scientific evidence, objectivity of data, relevance of evidence, data interpretation, coordination of theory and evidence, and repeated observation. Results showed that although many students recognized certain features of scientific inquiry such as objectivity of data, few of them understood why such features are valued and how to collect and use such data. In particular, students experienced difficulty in formulating explanation from evidence, not knowing, for example, that repeated observations are needed before making a general statement. The results of this study suggest that efforts to foster students' inquiry abilities need to be based on careful analyses of students existing inquiry skills and understanding.

Do We Have to Teach Intelligent Design along with Evolution in Public Schools? (학교에서 진화론과 함께 지적설계론도 가르쳐야 하는가)

  • Song, Kwang-Han
    • Journal of the Korea Convergence Society
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    • v.9 no.8
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    • pp.185-198
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    • 2018
  • This paper was written for the purpose of using as the theoretical basic data of judgment in the situation that there is a growing demand for intelligent design theory to be taught in public schools along with evolution theory. In order to verify the possibility that intelligent design theory, which has little empirical evidence unlike evolutionary theory, could be a scientific theory, what intelligence is and whether the trace of intelligence is actually found in nature was confirmed through literature. If intelligent elements, which are traces of intelligence in nature, are discovered empirically in nature, then intelligent design theory can be recognized as a scientific theory and can also be taught in public schools. The identity and traces of intelligence were found in relevant literature and the traces are found not only in various artificial products derived from human beings such as thinking, knowledge, and civilization, but also in all phenomena of nature. Based on these results, this paper provides a discussion on how the evolutionary theory and intelligent design theory should be handled in the field of school education, as well as how to resolve the conflicts between evolutionary theory and intelligent design theory.

Design and Implementation of a Learning Organization for Autonomous Biosafety Management of Infectious Disease Laboratories by Knowledge Translation (지식확산에 의한 감염병 실험실의 자율적 생물안전관리 학습조직 설계 및 실행)

  • Shin, Haeng-Seop;Yu, Minsu
    • Journal of Environmental Health Sciences
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    • v.41 no.2
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    • pp.102-115
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    • 2015
  • Objectives: A learning organization was designed and implemented on the basis of the selection criteria and essential elements of knowledge translation theory. Methods: The learning organization was designed on the basis of biosafety harmonization criteria and risk management strategy and was implemented as the learning organization for biosafety management by the National Institute of Health, Korea Centers for Disease Control & Prevention. The effect of knowledge translation in the research institutions by evidence-based policy was verified. Results: The result of applying the knowledge translation theory involving all stakeholders showed a positive reaction in establishing and implementing biosafety management strategy and embodied risk assessment criteria and evoked sympathy with the necessity of learning and using of expert knowledge about risk assessment and risk management. All stakeholders initiated voluntarily action toward new human-network construction and communication between similar organizations. The learning organization's capability expanded the base of knowledge translation. Conclusion: These results showed that a learning organization could enhance the autonomous safety management system by diffusion of knowledge translation.

Development of an Effective Strategy to Teach Evolution

  • Ha, Min-Su;Cha, Hee-Young
    • Journal of The Korean Association For Science Education
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    • v.31 no.3
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    • pp.440-454
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    • 2011
  • This study proposes a new instructional strategy and corresponding materials designed from various alternative frameworks to help students understand evolution as a biologically acceptable theory. Biology teachers have normally taught the evolutionary mechanism by means of comparing Lamarckism with natural selection. In this study, a new instructional strategy in which the Lamarckian explanation is first excluded because Lamarckism is known to be subsumed in a learner's cognitive structure as a strong preconception of evolution is suggested for teaching evolution. After mutation theory is introduced, Darwinism including natural selection is explained separately during the next class hour. Corresponding instructional materials that aid student understanding of the evolutionary mechanism were developed using recently published articles on human genetic traits as scientific evolutionary evidence instead of the traditional evolutionary subject matter, giraffe neck. Evolutionary evidence from human genetic traits allows students to exclude anthropocentric thoughts effectively and raise concern for the phenomenon of evolution positively. The administered instructional strategy and materials in this research improved student conception, concern, and belief of evolution and it is believed that they helped students understand the evolutionary mechanism effectively.

Involvement of Board Chairmen in Audit Committees and Earnings Management: Evidence from Malaysia

  • AL-ABSY, Mujeeb Saif Mohsen;ISMAIL, Ku Nor Izah Ku;CHANDREN, Sitraselvi;AL-DUBAI, Shehabaddin Abdullah A.
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.8
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    • pp.233-246
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    • 2020
  • This paper investigates the effect of the involvement of the board chairman in the audit committee (AC) on earnings management (EM). It examines Bursa Malaysia-listed companies with the lowest positive earnings for the years 2013 to 2015. The Modified Jones Model by Kasznik (1999) was used to determine discretionary accruals. An AC that includes its board chairman as an ordinary member is associated with greater discretionary accruals. However, a board chairman who is also the chairman of the AC does not seem to influence discretionary accruals. This paper supports the agency theory and policy-makers' efforts to prevent board chairmen from sitting on ACs. It is the first study that uses the agency theory to describe the association between the board chairman's involvement in the both AC and EM. This study alerts policy-makers, stakeholders and researchers to the influence of a board chairman serving on the AC in curbing EM. Furthermore, it provides empirical evidence that the majority of Malaysian companies whose board chairmen are involved in the AC appoint the chairman as an ordinary member of the AC. This indicates that executive directors may affect such actions. Hence, more policies are needed to improve AC independence.

Political Connections and CSR Disclosures in Indonesia

  • SARASWATI, Erwin;SAGITAPUTRI, Ananda;RAHADIAN, Yan
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.11
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    • pp.1097-1104
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    • 2020
  • This research seeks to provide evidence about how political connections, proxied by government ownership and the existence of politically connected board members, affect the extent of corporate social responsibility (CSR) disclosures in Indonesian listed companies. This research uses the legitimacy theory as a basis for explaining management's motivation for disclosing its CSR. The sample consists of 131 firm-year observations from 38 non-financial public companies that published sustainability reports from 2013 to 2017. We measured the CSR disclosures using a disclosure checklist on the sustainability reports. We subsequently processed the data using a random effect (RE) linear regression. The result shows that CSR disclosures were greater in government-owned companies but lower in companies that have politically connected board members. The results support the legitimacy theory that the government intends to demonstrate legitimate national economic and political conditions by showing that government-owned companies are sustainable. However, CSR disclosures seem to have a substitutive relationship with the existence of politically connected board members, since those political connections may protect the company from public pressure and/or the risk of litigation, reducing the need for CSR disclosures. This research provides evidence that different types of political connections may have different impacts on corporate disclosures.

The Effects of Home Country Government Support on International Business Performance: Evidence from Chinese Firms (본국 정부지원이 기업의 국제화 성과에 대한 효과: 중국기업을 대상으로 한 실증적 연구)

  • Zhang, Ruo-Nan;Oh, Han-Mo
    • Asia-Pacific Journal of Business
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    • v.9 no.1
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    • pp.91-106
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    • 2018
  • An appreciable number of Chinese firms have successfully expanded their businesses into foreign economics although they have limited resources. Advocating that home country government supports can mitigate firms' resource-disadvantages in international expansions, we attempted to investigate whether and how the Chinese government's support enables Chinese firms to compete in foreign markets. Based heavily on the knowledge-based theory of the firm and the resource-based theory of the firm, we developed a model that explain and predicts the effects of home-country government-supports on superior financial performance. The model was empirically tested using a accounting dataset regarding Chinese firms' 323 international expansion events from 2008 to 2015. Empirical evidence presents that the Chinese government's support has a positive effect on Chinese firms' international success and that these firms' marketing, technological, and managerial resources positively moderate the effect of the government support on the firms' international success. Nonetheless, because we employed an event-study method, the limitations of the method can be applied to the current research. In addition, because of the empirical context, the results of the research might lack generalizability. We, however, provided an understanding how firms from emerging countries can succeed in international expansions specifically when they have lack of resources for international competition.

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