• 제목/요약/키워드: causal

검색결과 3,950건 처리시간 0.035초

정량 추론과 정성 추론의 통합 메카니즘 : 주가예측의 적용 (A Mechanism for Combining Quantitative and Qualitative Reasoning)

  • 김명종
    • 지식경영연구
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    • 제10권2호
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    • pp.35-48
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    • 2009
  • The paper proposes a quantitative causal ordering map (QCOM) to combine qualitative and quantitative methods in a framework. The procedures for developing QCOM consist of three phases. The first phase is to collect partially known causal dependencies from experts and to convert them into relations and causal nodes of a model graph. The second phase is to find the global causal structure by tracing causality among relation and causal nodes and to represent it in causal ordering graph with signed coefficient. Causal ordering graph is converted into QCOM by assigning regression coefficient estimated from path analysis in the third phase. Experiments with the prediction model of Korea stock price show results as following; First, the QCOM can support the design of qualitative and quantitative model by finding the global causal structure from partially known causal dependencies. Second, the QCOM can be used as an integration tool of qualitative and quantitative model to offerhigher explanatory capability and quantitative measurability. The QCOM with static and dynamic analysis is applied to investigate the changes in factors involved in the model at present as well discrete times in the future.

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영역특정론과 영역일반론에 따른 유아의 인과추론 - 물리, 심리 영역을 중심으로 - (The Role of Domain-specific Causal Mechanism and Domain-general Conditional Probability in Young Children's Causal Reasoning on Physics and Psychology)

  • 김지현;이순형
    • 아동학회지
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    • 제29권5호
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    • pp.243-269
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    • 2008
  • The role of domain-specific causal mechanism information and domain-general conditional probability in young children's causal reasoning on physics and psychology was investigated with the participation of 121 3-year-olds and 121 4-year-olds recruited from seven child care centers in Seoul, Kyonggi Province, and Busan. Children watched moving pictures on physical and psychological phenomena, and were asked to choose an appropriate cause and justify their choice. Results showed that young children's causal reasoning differed depending on domain-specific mechanism. In addition, their causal reasoning on physics and psychology differed by the developmental level of causal mechanism. The interaction of domain-specific mechanism and domain-general conditional probability influenced children's causal reasoning : evident conditional probability between domain-appropriate cause and effect helped children make more inferences based on domain-specific causal mechanism.

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A Causal Knowledge-Driven Inference Engine for Expert System

  • 이건찬;김현수
    • 한국지능시스템학회논문지
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    • 제8권6호
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    • pp.70-77
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    • 1998
  • Although many methods of knowledge acquisition has been developed in the exper systems field, such a need form causal knowledge acquisition hs not been stressed relatively. In this respect, this paper is aimed at suggesting a causal knowledge acquisition process, and then investigate the causal knowledge-based inference process. A vehicle for causal knowledge acquisition is FCM (Fuzzy Cognitive Map), a fuzzy signed digraph with causal relationships between concept variables found in a specific application domain. Although FCM has a plenty of generic properties for causal knowledge acquisition, it needs some theoretical improvement for acquiring a more refined causal knowledge. In this sense, we refine fuzzy implications of FCM by proposing fuzzy causal relationship and fuzzy partially causal relationship. To test the validity of our proposed approach, we prototyped a causal knowledge-driven inference engine named CAKES and then experimented with some illustrative examples.

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Fuzzy Causal Knowledge-Based Expert System

  • Lee, Kun-Chang;Kim, Hyun-Soo;Song, Yong-Uk
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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    • pp.461-467
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    • 1998
  • Although many methods of knowledge acquisition has been developed in the expert systems field, such a need for causal knowledge acquisition has not been stressed relatively. In this respect, this paper is aimed at suggesting a causal knowledge acquisition process, and then investigate the causal knowledge-based inference process. A vehicle for causal knowledge acquisition is FCM (Fuzzy Cognitive Map), a fuzzy signed digraph with causal relationships between concept variables found in a specific application domain. Although FCM has a plenty of generic properties for causal knowledge acquisition, it needs some theoretical improvement for acquiring a more refined causal knowledge. In this sense, we refine fuzzy implications of FCM by proposing fuzzy implications of FCM by proposing fuzzy causal relationship and fuzzy partially causal relationship. To test the validity of our proposed approcach, we prototyped a causal knowledge-driven inference engine named CAKES and then experime ted with some illustrative examples.

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Causality, causal discovery, causal inference and counterfactuals in Civil Engineering: Causal machine learning and case studies for knowledge discovery

  • M.Z. Naser;Arash Teymori Gharah Tapeh
    • Computers and Concrete
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    • 제31권4호
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    • pp.277-292
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    • 2023
  • Much of our experiments are designed to uncover the cause(s) and effect(s) behind a phenomenon (i.e., data generating mechanism) we happen to be interested in. Uncovering such relationships allows us to identify the true workings of a phenomenon and, most importantly, to realize and articulate a model to explore the phenomenon on hand and/or allow us to predict it accurately. Fundamentally, such models are likely to be derived via a causal approach (as opposed to an observational or empirical mean). In this approach, causal discovery is required to create a causal model, which can then be applied to infer the influence of interventions, and answer any hypothetical questions (i.e., in the form of What ifs? Etc.) that commonly used prediction- and statistical-based models may not be able to address. From this lens, this paper builds a case for causal discovery and causal inference and contrasts that against common machine learning approaches - all from a civil and structural engineering perspective. More specifically, this paper outlines the key principles of causality and the most commonly used algorithms and packages for causal discovery and causal inference. Finally, this paper also presents a series of examples and case studies of how causal concepts can be adopted for our domain.

인과지도의 타당성 확보와 정보 표현력 향상을 위한 연구 (A Study on Ensuring Validity and Increasing Power of Expression on Causal Maps)

  • 정재운;김현수
    • 한국시스템다이내믹스연구
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    • 제8권1호
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    • pp.97-115
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    • 2007
  • In System Dynamics, causal maps are used as a tool for analyzing dynamic problems and discussing the outcome of analyzed problems. However there are some limitations to use causal maps. In the drawing phase of causal maps, the high abstraction of variables that constitutes problems makes it difficult to find out correct information. And principles or rules to check errors on causal maps are not sufficient yet. Moreover, simulation modeling tasks are required to be concerned separately from drawing causal maps because causal maps cannot provide enough information to simulation modeling. In order to overcome these limitations, this study shows ways that ensure validity, increase power of expression of causal maps and improve the connection between causal maps and simulation modeling.

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Dissipation Effect in Causal Maps as a Source of Communication Problem

  • Kim, Dong-Hwan
    • 한국시스템다이내믹스연구
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    • 제6권1호
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    • pp.5-15
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    • 2005
  • This paper investigates psychological differences between constructors and interpreters of causal maps. This paper argues that dissipation effects and dilution effects applies to those who are to interpret causal maps not to those who construct them. Dissipation effects are psychological tendency that people perceive causal effect as weak as the number of causal links increases. Dilution effects occur when people undervalue the strength of causal relation as the number of causal variables increases. Experimental results show that concentration effects opposite to the dissipation effects and dilution effects explain more correctly the perception of constructors of causal maps. This paper points out that this asymmetric psychological tendencies between constructors and interpreters of causal maps is the psychological source of the communication problems between systems thinkers and their clients.

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An Inquiry to the Causal Perceptions & Health Seeking Behaviors of Rheumatoid Arthritis Patients

  • Kim, Boon-Han;Kim, Hung-Kyu;Yun Jung;Kang, Hwa-Jeong
    • 대한간호학회지
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    • 제29권5호
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    • pp.1001-1010
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    • 1999
  • This study was undertaken to investigate the causal perceptions and health seeking behaviors of Rheumatoid arthritis patients, define and understand the typology, and find the relationship between causal perceptions and health seeking behavioral types. There were six types(Physical Fatigue, Dispensation of Nature, Causality to Environment, Conscience of Guilty, Rationally perceiving, Psychological Stress) of subjective opinion about Causal Perceptions of Rheumatoid Arthritis Patients. And there were four types(Oriental medical Treatment, Information Seeking, Dietary Control. Western Medical Treatment) of subjective opinion about Health Seeking Behaviors. In the relationship between types of the causal perceptions and health seeking behaviors, oriental medical treatment and information seeking type were common health seeking behaviors of all six causal perception types. Only difference for internal causal perception types was related to hospital instructions and external causal perception types were related to dietary control. The result of this study can help health care providers, especially nurses to understand the types of causal perceptions and health seeking behaviors of Rheumatoid arthritis patients to gain treatment compliance from patients according to their causal perceptions of the illness, and use it to develop educational nursing intervention to aid health care.

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심리와 생물 영역에서의 유아의 인과추론 : 영역특정성과 영역일반성의 상호작용 (Young Chilldren's Causal Reasoning on Psychology and Biology : Focusing on the Interaction between Domain-specificty and Domain-generality)

  • 김지현
    • 가정과삶의질연구
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    • 제26권5호
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    • pp.333-354
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    • 2008
  • This study aimed to investigate the role of domain-specific causal mechanism information and domain-general conditional probability in young children's causal reasoning on psychology and biology. Participants were 121 3-year-olds and 121 4-year-olds recruited from seven childcare centers in Seoul, Kyonggi Province, and Busan. After participants watched moving pictures on psychological and biological phenomena, they were asked to choose appropriate cause and justify their choices. Results of this study were as follows: First, young children made different inferences according to domain-specific causal mechanisms. Second, the developmental level of causal mechanisms has a gap between psychology and biology, and biological knowledge was proved to be separate from psychological knowledge during the preschool period. Third, young children's causal reasoning was different depending on the interaction effect of domain-specific mechanisms and domain-general conditional probability: children could make more inferences based on domain-specific causal mechanisms if conditional probability between domain-appropriate cause and effect was evident. To conclude, it can be inferred that the role of domain-specific causal mechanisms and domain-general conditional probability is not competitive but complementary in young children's causal reasoning.

인과적 마코프 조건과 비결정론적 세계

  • 이영의
    • 논리연구
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    • 제8권1호
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    • pp.47-67
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    • 2005
  • 베이즈망은 탐구 공간을 구성하는 변수들 사이에 성립하는 확률적 관계를 이용하여 그 변수들 사이에 성립된다고 가정되는 인과 관계를 추론하는데 이용된다. 베이즈망에 관한 철학적 논쟁의 대상은 특정한 변수들의 확률적 독립성을 가정하는 인과적 마코프 조건이다. 베이즈망 이론에 대한 강력한 비판자인 카트라이트는 인과적 마코프 조건이 비결정적 세계에서는 성립될 수 없기 때문에 인과적 추리에 대한 타당한 원리가 될 수 없다고 주장한다. 이글의 목적은 인과적 마코프 조건이 인과적 추리에 대한 타당한 원리가 될 수 없다는 카트라이트의 비판이 타당한가를 검토하는 것이다. 나는 인과적 사건들의 연쇄를 허용하는 연속모델은 카트라이트의 비판을 벗어날 수 있다고 주장한다.

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