• 제목/요약/키워드: Causal Model

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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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동태적 분석 및 설계를 위한 인과지도 작성법의 한계와 개선방안에 관한 연구 (A Study on Theoretical Improvement of Causal Mapping for Dynamic Analysis and Design)

  • 정재운;김현수
    • 한국시스템다이내믹스연구
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    • 제10권1호
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    • pp.33-60
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    • 2009
  • This study explores the limitation in making a causal model through an existing case and proposes an alternative plan to improve a theoretical system of causation modeling. To make a dynamic and actual model, several principles are needed such as reality based analysis of system structures and dynamics, consistent expression of causations, conversion of numerical formulas to causal relations, classification and arrangement of variables by size of concept, etc. However, it is hard to find cases to apply these considerations from existing models in System Dynamics. Therefore, this study verifies errors of derived models from literatures and proposes principles and guides that should be considered to make a sound dynamic model on a causal map. It contributes to making an opportunity for exciting public opinion to improve theory about causal maps, yet it has limitation that the study does not advance forward to the experimental step. For future study, it plans to make up by classifying and leveling causal variables, developing a dynamic BSC model.

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균형성과표를 활용한 전자의무기록시스템의 성과측정 모형개발 (Development of the Performance Measurement Model of Electronic Medical Record System - Focused on Balanced Score Card -)

  • 이경희;김영훈;부유경
    • 한국병원경영학회지
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    • 제21권4호
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    • pp.1-12
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    • 2016
  • The purpose of this study are suggest to performance measurement model of Electronic Medical Record(EMR) and Key Performance Index(KPI). For data collection, 665 questionnaires were distributed to medical record administrators and insurance reviewers at 31 hospitals, and 580 questionnaires were collected(collection rate: 87.2%). Regarding methodology, Critical Success Factor(CSF) and index of the information system were derived based on previous studies, and these were set as performance measurement factors of EMR system. The performance measurement factors were constructed by perspective using BSC, and analysis on causal relationship between factors was conducted. A model of causal relationship was established, and performance measurement model of EMR system was proposed through model validation. Analysis on causal relationship between performance management factors revealed that utility cognition of the learning & growth perspective factor had causal relationship with job efficiency(${\beta}=0.20$) and decision support(${\beta}=0.66$) of the internal process perspective factors, and security had causal relationship with system satisfaction(${\beta}=0.31$) of the customer perspective factor. System quality had causal relationship with job efficiency(${\beta}=0.66$) and decision support(${\beta}=0.76$) of the internal process perspective factors, all of which were statistically significant(P<0.01). Job efficiency of the internal process perspective had causal relationship with system satisfaction(${\beta}=0.43$), and decision support had causal relationship with decision support satisfaction(${\beta}=0.91$) and job satisfaction (${\beta}=0.74$), all of which were statistically significant(P<0.01). System satisfaction of the customer perspective had causal relationship with job satisfaction(${\beta}=0.12$), job satisfaction had causal relationship with cost reduction(${\beta}=0.53$) of the financial perspective, and decision support satisfaction had causal relationship with productivity improvement(${\beta}=0.40$)of the financial perspective(P<0.01). Also, cost reduction of the financial perspective had causal relationship with productivity improvement(${\beta}=0.37$), all which were statistically significant(P<0.05). Suitability index verification of the performance measurement model whose causal relationship was found to be statistically significant revealed that $X^2/df=2.875$, RMR=0.036, GFI=0.831, AGFI=0.810, CFI=0.887, NFI=0.838, IFI=0.888, RMSEA=0.057, PNFI=0.781, and PCFI=0.827, all of which were in suitable levels. In conclusion, the performance measurement indices of EMR system include utility cognition, security, and system quality of the learning & growth perspective, decision support and job efficiency of the internal process perspective, system satisfaction, decision support satisfaction, and job satisfaction of the customer perspective, and productivity improvement and cost reduction of the financial perspective. In this study, it is expected that the performance measurement indices and model of EMR system which are suggested by the author, will be a measurement tool available for system performance measurement of EMR system in medical institutions.

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.

세 사건간의 인과관계 판단 (Inferring the Causal Relationship between Three Events)

  • 도경수;최재혁
    • 인지과학
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    • 제21권1호
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    • pp.47-75
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    • 2010
  • 인과도식에 의한 하향처리 과정과 빈도 자료 해석에 의한 상향처리 과정이 어떻게 작동하는 지를 알아보기 위해, 세 사건들의 빈도 자료를 주고 인과관계를 판단하게 하였다. 중성 사건들을 주고 판단하게 한 실험 1에서는 Or 구조의 정답율이 높았다. 인과도식 정보와 빈도자료를 주고 판단하게 한 실험 2에서는 Or 구조의 정답율이 높았고, 인과도식과 빈도자료가 일치할 때 정답율이 높았다. 정반응 수와 오반응 수를 대상으로 반응에 이르는 인지과정을 이산적인 과정들의 조합으로 가정하는 Multinomial Processing Tree Modeling을 실시하였다. 모델 피팅 결과 사람들이 빈도자료를 이용하여 인과 구조를 판단할 때 기본적으로 작동하는 인과 도식이 Or 구조라는 점을 시사하는 결과를 얻었다.

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이동통신 단말기의 감성만족 요소간 인과관계에 관한 연구 (A Study on Causal Relationships among Sensibility Satisfaction Factors for Mobile Phone)

  • 전영호;백인기;김정일;손기혁
    • 대한인간공학회지
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    • 제22권2호
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    • pp.1-13
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    • 2003
  • In general, causal relationship for theoretical concepts is hypothesized based on precedent studies and tested by a structural equation model. However, when theoretical backgrounds are scarce or absent, the causal relationship is hypothesized operatively by the purpose and scope of research and tested by overall goodness-of-fit indices such as GFI and RMR. Such a causal relationship can't be most appropriate statistically because it is selected as specific relationship from researcher's view among possible causal relationships. Therefore, this study is to propose a procedure for identifying the causal relationship that produces the best GFI among possible causal relationships for theoretical concepts.

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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시스템 다이내믹스를 활용한 마을만들기 모형구축 연구 (A Study on the Community Planning Model Using for System Dynamics)

  • 양원모;장준호;여관현
    • 한국시스템다이내믹스연구
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    • 제14권3호
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    • pp.75-103
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    • 2013
  • The purpose of this study is to use system dynamics to establish the relation among each variable through the construction process of Community Planning Model, and examine what changes policy scenarios per alternative cause in Community Planning through policy simulation of the constructed model. Therefore, this study extracted chief variables of Community Planning Projects through precedent researches related to Community Planning, and extracted variables were prepared as causal map to examine in what causal cycle feedback structure within Community Planning they can be explained. Next, Community Planning Model was constructed based on the prepared causal map. The model was verified by specialists' interviews and simulation of example areas. This study, which aimed to construct Community Planning Model using system dynamics, has a significance in that it prepared the foundation to provide useful methodology in monitoring the progress of project or establishing the plan of future Community Planning Projects.

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비실험 자료로부터의 인과 추론: 핵심 개념과 최근 동향 (Causal inference from nonrandomized data: key concepts and recent trends)

  • 최영근;유동현
    • 응용통계연구
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    • 제32권2호
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    • pp.173-185
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    • 2019
  • 과학적 연구에서 핵심적인 연구 주제 또는 가설은 대부분 인과적 질문(causal question)을 포함한다. 예를 들어, 전염병 예방을 위한 치료법의 효과 연구, 특정 정책의 시행으로 인한 효용(utility)의 평가에 대한 연구, 특정 사용자를 대상으로 노출된 광고의 종류에 따른 광고의 효과성에 대한 연구는 모두 인과 관계(causal relationship)의 추론이 요구된다. 이러한 인과 관계를 다루는 통계적 인과 추론(statistical causal inference)의 주요 관심사 중 하나는 모집단에 일종의 개입(정책 혹은 처치)을 적용한 후 개입의 효과를 정확하게 추정하는 것이다. 인과 추론은 임상실험과 정책결정에서 주로 이용되었으나, 이른바 빅데이터 시대의 도래로 가용한 관측자료가 폭발적으로 증가하였고 이로 인하여 인과 추론에 대한 잠재적 응용가치와 수요가 지속적으로 증가하고 있다. 하지만 가용한 대부분의 자료는 임의실험 기반의 자료와 달리 개입이 임의로 분배되지 않은 비실험 관측자료이다. 따라서, 본 논문은 비실험 관측자료로부터 개입의 효과를 추정하기 위한 인과 추론의 핵심 개념과 최근의 연구동향을 소개하고자 한다. 이를 위하여 본문에서는 먼저 개입의 효과를 Neyman-Rubin의 잠재 결과(potential outcome) 모형으로 나타내고, 개입의 효과를 추정하는 여러 접근법 중 특히 성향점수(propensity score) 기반 추정법과 회귀모형 기반 추정법을 중점적으로 소개한다. 최근 연구동향으로는 (1) 평균 효과 크기 추정을 넘어선 개인별 효과 크기의 추정, (2) 효과크기 추정에 있어서 자료 규모의 증대로 인한 차원의 저주가 야기하는 난제들과 이에 대한 해결방안들, (3) 복합적 인과관계를 반영하기 위한 Pearl의 구조적 인과 모형(structural causal model) 및 잠재 결과 모형과의 비교의 3가지 주제로 구분하여 소개한다.

도시보건소 공무원의 조직몰입도 인과요인에 관한 연구 - 한 가설적 인과모형분석을 통해 - (A Study on Causal Factors of Organizational Commitment of Public Servants in Urban Health Centers: Testing a Hypothetical Canusal Model)

  • 이상준;김창엽;김용익;신영수
    • 보건행정학회지
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    • 제8권1호
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    • pp.52-96
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    • 1998
  • To find causal factors and improvement plans of organizational commitment of public servants in urban health centers, a hypothetical causal model, which included 2 endogenous variables(organizational commitment & organizational satisfaction) and 15 exogenous variables, was constructed. Exogenous variables consisted of individual factors (sex, age, education, job-grade, and annual salary), psychological variables(pride for organization, extrinsic motivation, intrinsic motivation and support of supervisor) ad structural variables(formalization, centralization, communication, job-conflict, job-decision, and workload). In the hypothetical causal model, organizational commitment was supposed to be effect variable, and organizational satisfaction was presumed to be intervening variable to mediate between organizational commitment and exogenous variables. For data collection, cross-sectional self-administered questionnaire survey was conducted to 1,295 public servants from 32 urban health centers nationwide. The survey responses were from 934, 72.1% of subjects. But 756 responses(58.4%) were analyzed because of excluding ones with missing values. The hypothetical causal model was fitted by covariance structural analysis with maximum likelihood method. Main results were as follows: (1) The fitted causal model accounted for 33 and 55 percent of total variance of organizational commitment and organizational satisfaction of public servants, respectively. (2) In order of effect size, pride for organization, supervisor support, communication, extrinsic motivation and centralization had an indirect effect effect on organizational commitment through organizational satisfaction. However, the effect of centralization was negative. (3) Pride for organiztion, intrinsic motivation, organizational satisfaction, job-conflict, supervisor support, communication, age, centralization, annual salar and extrinsic motivation had indirect or direct effects on organizational commitment in order of effect size. Among them, effects of job-conflict and centraldization were negative. In conclusion, these results suggested that organizational commitment of public servants in urban health centers could be enhanced by pride for organization, intrinsic and extrinsic motivations, prevention of job-conflict and excess centralization, supervisor support and active communication. Especially, pride for organization and intrinsic motivation were expected to play the most important role.

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