• Journal of Preventive Medicine and Public Health
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• 제40권6호
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• pp.495-504
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• 2007

Objectives : This study attempts to show how studies using non-experimental data can strengthen causal inferences by applying propensity score and instrumental variable methods based on the counterfactual framework. For illustrative purposes, we examine the effect of having private health insurance on the probability of experiencing at least one hospital admission in the previous year. Methods : Using data from the 4th wave of the Korea Labor and Income Panel Study, we compared the results obtained using propensity score and instrumental variable methods with those from conventional logistic and linear regression models, respectively. Results : While conventional multiple regression analyses fail to identify the effect, the results estimated using propensity score and instrumental variable methods suggest that having private health insurance has positive and statistically significant effects on hospital admission. Conclusions : This study demonstrates that propensity score and instrumental variable methods provide potentially useful alternatives to conventional regression approaches in making causal inferences using non-experimental data.

• 근관절건강학회지
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• 제2권2호
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• pp.168-184
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• 1995

This deductive-survey study was undertaken in order to examine if there were relationship between causal perceptions, expectation for the cure and compliance. The sampling method was a non-probability, purposive sampling technique. The participants of this study was 195 volunteers 1) who have been diagnosed as having chronic arthritis and 2) who were at the rheumatis center of one university hospital in Seoul between September 18th to September 25th 1989. This instruments used for this study were the compliance scale developed by Choi and causal perception scale developed by the researcher. Analysis of data was done using pass analysis, Pearson correlation coefficient. The result of study were as follow : Hypothesis 1 : "It's correlated that causal perception, expectation for cure and compliance" was accepted. (F=4.85, p< .05) Hypothesis 2 : "It's correlated that causal perception, expectation for cure and with depression" was partially accepted. Total age group-worry and anxiety (r=.1580, p<.001) After 40-function of immunity (r=.1731, p<.05) warry and anxiety (r=.1730, p<.001). In the relationship between general characteristics and the variables, age group correlated with compliance and causal perception.

• 통상정보연구
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• 제8권4호
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• pp.209-227
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• 2006

This paper analyse current interpretation of the "causal link" that in particular, focuses principally on the so-called "non-attribution" requirement of Article 4.2(b) of the Safeguards Agreement. The safeguard measures are justified as a temporary economic adjustment to harm that is caused by an increase in imports. The problem with this justification is that there are other kinds of economic forces that may injure domestic industries, such as changes in consumer tastes, government spending or a lack thereof, and economic downturns. These problems do not justify government-imposed remedies. When factors therefore other than increased imports are causing injury to the domestic industry at the same time, such injury shall not be attributed to increased imports. The Appellate Body stressed that a contribution of third-party imports to the existence of serious injury must be sufficiently clear as to establish the existence of the causal link required, it found that Article 4.2(b) does not suggest that increased imports be the sole cause of the serious injury, or that other factors causing injury must be excluded from the determination of serious injury. The interest in separation is to ensure that a measure is not applied to remedy harm not caused by imports, but this basic point assumes that the harm is distinguishable in the first place. It also assumes that the safeguard is designed to respond to harm caused by imports. In fact safeguards were never intended to respond to this kind of unfair trade, but rather to provide whatever emergency relief might assist an ailing domestic industry if imports happened to be a part of that injury. The Appellate Body's insistence in breaking cause and effect down to minutia in the non-attribution analysis seems to be so overly intricate that it conflicts with it's broader focus on evaluating factors that effect harm on the industry as a whole.

• 산학경영연구
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• 제20권2호
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• pp.119-133
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• 2007

본 연구는 경영혁신의 한 기법으로 BSC를 비영리기업인 대학병원에 도입할 경우 영리기업에서와 같이 그 효과가 있는지를 검증하고자 한다. 대학병원 사례에 의한 BSC 성과측정지표간의 인과관계를 알아보기 위하여 구조방정식 모델을 이용하여 분석하였다. BSC 성과측정지표간의 인과관계를 분석한 결과 모두 통계적으로 유의한 것으로 나타나 연구가설이 모두 채택되었다. 향후에는 실제 재무자료를 학습 및 성장 관점, 내부프로세스 관점, 고객 관점과 연계하여 BSC 성과측정지표간의 인과관계를 연구할 필요가 있다.

• 한국사회복지학
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• 제65권2호
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• pp.203-230
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• 2013

본 연구는 한국복지패널의 원자료를 cross-lagged panel design에 따라 분석자료를 추출하고 인과관계 분석 모형을 이용하여 음주문제와 우울의 인과관계를 분석하였다. 나아가 빈곤이 음주문제와 우울에 영향을 미친다는 국내외 선행연구들을 바탕으로, 음주문제와 우울 간의 인과관계와 빈곤 상태의 변화가 연관성이 있는지를 살펴보았다. 연구 대상은 한국복지패널의 1차년도와 2차년도의 자료에서 반복측정된 3,976명의 성인 남녀였으며, 인과관계 분석은 McArdle and Hamagami (2001)에 의해서 정립된 Latent Difference Scores (LDS)모델을 사용하였다. 분석단계에서는 먼저 음주문제와 우울의 인과관계를 밝힌 후에, 이러한 인과관계가 빈곤의 상태변화를 나타내는 4개의 하위집단 (빈곤 지속 집단, 빈곤 탈출 집단, 비빈곤 지속 집단, 빈곤시작 집단)에서 유지되는지를 분석하였다. 분석결과 연구대상전체를 이용한 LDS모델의 결과는 우울이 음주문제의 변화를 예측할 뿐 아니라 음주 역시 우울의 변화를 예측하는 것으로 나타나 우울과 음주가 상호 인과관계를 갖는 것으로 나타났다. 전체 연구 대상자를 빈곤 상태 변화에 따른 집단으로 구분하여 분석한 결과 빈곤지속 집단에서는 우울과 음주가 상호 인과관계를 갖는 것으로 나타났고, 빈곤 시작 집단과 비빈곤 지속 집단에서는 우울의 음주 변화에 선행하는 요인으로 나타났다. 그러나 빈곤 탈출 집단에서는 음주와 우울 사이의 인과관계가 나타나지 않았다. 본 연구의 결과는 음주와 우울 사이의 인과관계가 빈곤상태변화에 따라 다르게 나타날 수 있음을 체계적으로 보여주는 새로운 결과로서 기존의 횡단연구들에서 우울과 음주의 관계에 대한 서로 상충하는 다양한 결과들에 대한 종합적 설명을 제공할 수 있다는 의미가 있다.

• 품질경영학회지
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• 제37권1호
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• pp.10-19
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• 2009

The objective of this study is to analyze the causal relationship among Non-profit Criteria of the Malcolm Baldrige National Quality Award(MBNQA) and to compare the casuality among company, hospital and non-profit organization field. The survey instrument consists of 94 questions from the seven categories of the MBNQA. Structural Equation Modeling (SEM) is used to analyze the empirical data and estimates the path coefficients among the MBNQA categories. The result of our research is as follows, First, the Leadership effects on as a driver of all factors. Secondly, the positive effect of the Foundation on the Direction and the System categories, Finally, the positive influence of the Direction on the System categories of the MBNQA model. In this study, most hypothesis are statistically significant.

• 한국컴퓨터정보학회논문지
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• 제20권7호
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• pp.115-120
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• 2015

The old people's feelings, emotions, and self-evaluative judgements fluctuate overtime. The purpose of this paper is to proof relations among well-being factors in social activity. Major results of this paper was as follows. First, the social activity participated elderly had higher health status, self-esteem, mental-health, and successful aging than the non-participated elderly. Second, self-esteem and mental health were exposed as important variable for all of the two groups to improve the successful aging. Thus, self-esteem and mental health can become significant indicator of self-empowering and psychological resilience. Third, the strongest total causal effect of successful aging was health status in social activity participated elderly, while self-esteem was the greatest total causal effect of it in the non-participated elderly. Health status had higher indirect effect of successful aging than direct effect of it in both of them.

• 응용통계연구
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• 제36권2호
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• pp.129-139
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• 2023

변동성의 예측은 자산의 리스크에 대비하는 데에 중요한 역할을 하기때문에 필수적이다. 인공지능을 통하여 이러한 복잡한 특성을 지닌 변동성 예측을 시도하였는데 기존 시계열 예측에 적합하다 알려진 LSTM (1997)과 GRU (2014)은 기울기 소실로 인한 문제, 방대한 연산량의 문제, 그로 인한 메모리양의 문제 등이 존재하였다. 변동성 데이터는 비정상성(non-stationarity)과 정상성(stationarity)을 모두 가지고 있는 특성이 있으며, 자산 가격 하방 쇼크에 더 큰 폭으로 상승하는 비대칭성과 상당한 장기 기억성, 시장에 큰 사건이 발생할 때 기존의 값들에 비해 이상치라 할 수 있을 정도의 예측할 수 없는 큰 값이 발생하는 특성들이 존재한다. 이렇게 여러 가지 복잡한 특성들은 하나의 모형으로 구조화되기 어려워서 전통적인 방식의 모형으로는 변동성에 대한 예측력을 높이기 어려운 면이 있다. 이러한 문제를 해결하기 위해 1D CNN의 발전된 형태인 causal TCN (causal temporal convolutional network) 모형을 변동성 예측에 적용하고, 예측력을 최대화 할 수 있는 TCN 구조를 설계하고자 하였다. S&P 500, DJIA, Nasdaq 지수에 해당하는 변동성 지수 VIX, VXD, and VXN, 에 대하여 예측력 비교를 하였으며, TCN 모형이 RNN 계열의 모형보다도 전반적으로 예측력이 높음을 확인하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1999년도 추계학술대회 및 정기총회 : 정보통신기술의 활용과 21세기 전자상거래
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• pp.42-46
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• 1999

Knowledge management(KM) is emerging as a robust management mechanism with which an organization can remain highly intelligent and competitive in a turbulent market. Organization memory(or knowledge) is at the heart of KM success. How to create organizational memory has been debated among researchers. In literature, a wide variety of methods for creating organizational memory have been proposed only to prove that its applicability is limited to decision-making problems which require shallow or non-causal knowledge type. However, organizational memory with a sense of causal knowledge is highly required in solving complicated decision-making problems in which complex dynamics exist between various factors and influence each other with cause and effect relationship among them. In this respect, we propose a new approach to creating a causal-typed organizational memory (CATOM), which has a form of causal knowledge and is represented in a matrix form, by using an inference diagram. An algorithm for CATOM creation is suggested and applied to an illustrative example. Results show that our proposed KM approach can effectively equip an organization with semi-automated CATOM creation and inference process which is deemed useful in a highly competitive business environment.

• Wind and Structures
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• 제19권5호
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• pp.467-480
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• 2014

The estimation of wind speed values used in codes and standards is an integral part of the wind load evaluation process. In a number of codes and standards, wind speeds outside of tropical cyclone prone regions are estimated using a single probability distribution developed from observed wind speed data, with no distinction made between the types of causal wind hazard (e.g., thunderstorm). Non-tropical cyclone wind hazards (i.e., thunderstorm, non-thunderstorm) have been shown to possess different probability distributions and estimation of non-tropical cyclone wind speeds based on a single probability distribution has been shown to underestimate wind speeds. Current treatment of non-tropical cyclone wind hazards in worldwide codes and standards is touched upon in this work. Meteorological data is available at a considerable number of United States (U.S.) stations that have information on wind speed as well as the type of causal wind hazard. In this paper, probability distributions are fit to distinct storm types (i.e., thunderstorm and non-thunderstorm) and the results of these distributions are compared to fitting a single probability distribution to all data regardless of storm type (i.e., co-mingled). Distributions fitted to data separated by storm type and co-mingled data will also be compared to a derived (i.e., "mixed") probability distribution considering multiple storm types independently. This paper will analyze two extreme value distributions (e.g., Gumbel, generalized Pareto). It is shown that mixed probability distribution, on average, is a more conservative measure for extreme wind speed estimation. Using a mixed distribution is especially conservative in situations where a given wind speed value for either storm type has a similar probability of occurrence, and/or when a less frequent storm type produces the highest overall wind speeds. U.S. areas prone to multiple non-tropical cyclone wind hazards are identified.