• 한국신뢰성학회지:신뢰성응용연구
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• 제16권4호
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• pp.323-330
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• 2016

Purpose: Recently, propensity score matching method is used in a large number of research paper, nonetheless, there is no research using fitness test of before and after propensity score matching. Therefore, comparing fitness of before and after propensity score matching by logistic regression analysis using data from 'online survey of adolescent health' is the main significance of this research. Method: Data that has similar propensity in two groups is extracted by using propensity score matching then implement logistic regression analysis on before and after matching separately. Results: To test fitness of logistic regression analysis model, we use Model summary, -2Log Likelihood and Hosmer-Lomeshow methods. As a result, it is confirmed that the data after matching is more suitable for logistic regression analysis than data before matching. Conclusion: Therefore, better result which has appropriate fitness will be shown by using propensity score matching shows better result which has better fitness.

• 대한치과의사협회지
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• 제58권3호
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• pp.152-168
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• 2020

The propensity score matching method is a statistical method used to reduce selection bias in observational studies and to show effects similar to random allocation. There are many observational studies in dentistry research, and differences in baseline covariates between the control and case groups affect the outcome. In order to reduce the bias due to confounding variables, the propensity scores are used by equating groups based on the baseline covariates. This method is effective, especially when there are many covariates or the sample size is small. In this paper, the propensity score matching method was explained in a simple way with a dental example by using R software. This simulated data were obtained from one of retrospective study. The control group and the case group were matched according to the propensity score and compared before and after treatment. The propensity score matching method could be an alternative to compensate for the disadvantage of the observation study by reducing the bias based on the covariates with the propensity score.

• 한국학교수학회논문집
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• 제18권1호
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• pp.149-167
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• 2015

본 연구의 목적은 수학의 학업성취도에 미치는 영향요인에 대하여 기존의 연구들을 분석하고, 특히 학교수준에서 실시하고 있는 수학과 수준별 이동수업이 실질적으로 학생들의 수학 학업성취도에 영향을 미치는지를 실증적으로 분석하고자 한다. 선택편의를 최소화하기 위해 한국교육종단연구2005의 6차년도 데이터를 바탕으로 경향점수매칭법(propensity score matching)을 사용하여 수학 교과 수준별 이동수업이 수학성취도의 지표인 수능 수리영역 표준점수에 미치는 영향을 살펴보았다. 그 결과 수준별 이동수업과 수학성취도 사이의 양의 관계가 있음을 확인하였으며, 수준별 이동수업의 효과적 운영을 위해 정책적인 노력이 요구된다.

• 대한암한의학회지
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• 제27권1호
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• pp.25-36
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• 2022

The Randomized Control Trial (RCT) is the most well-established and widely used statistical methodology in clinical research; however, applying thorough RCT to cancer patients presents challenges such as ethical concerns, high costs, short clinical periods, and limitations in collecting various side effects. To address this issue, the propensity score matching method, which takes advantage of the benefits of observational research while compensating for the drawbacks of randomized control trials, is used in a variety of fields. In recent years, 28 studies on the effectiveness of Korean medicine on tumors have been conducted abroad using the Propensity Score Matching Method, but none have been conducted in Korea. The majority of studies have focused on liver cancer, colon cancer, lung cancer, and stomach cancer, with endpoints such as survival time, incidence rate, quality of life, and treatment outcomes revealing statistical differences in how Korean medicine intervention affects treatment outcomes. As a result, well-established studies using the propensity matching score methodology should be useful in evaluating the impact of Korean medicine in oncology treatments.

• 사회복지연구
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• 제37호
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• pp.171-197
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• 2008

본 연구는 국민기초생활보장법 하의 조건부 수급자가 자활직업훈련 프로그램의 참여로 인해 임금이 향상되었는지에 관해 실증적으로 분석 하였다. 분석 자료로는 한국노동연구원에서의 자활사업 참여자를 대상으로 한 '자활대상자 직업훈련 실태'조사와 한국보건사회연구원에서 실시하는 2004년 '자활패널'조사 자료를 결합하여 '자활직업훈련 실태'조사의 응답자를 실험그룹으로'자활패널'을 비교그룹으로 구성하여 분석하였으며, 기존 연구의 통계적 취약점을 극복하기 위해 Propensity Score Matching 방법을 이용하여 자활직업훈련의 임금효과를 분석하였다. 분석 결과 자활직업훈련 참가자들이 그와 비슷한 특성을 가진 비교그룹에 비해서 약 12만원 정도 소득이 낮음을 확인함으로써, 이러한 부정적인 효과가 나타난 원인과 의미에 대해서 논의하였다.

• Communications for Statistical Applications and Methods
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• 제30권1호
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• pp.1-19
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• 2023

Observational data with missing or incomplete data are common in biomedical research. Multiple imputation is an effective approach to handle missing data with the ability to decrease bias while increasing statistical power and efficiency. In recent years propensity score (PS) matching has been increasingly used in observational studies to estimate treatment effect as it can reduce confounding due to measured baseline covariates. In this paper, we describe in detail approaches to competing risk analysis in the setting of incomplete observational data when using PS matching. First, we used multiple imputation to impute several missing variables simultaneously, then conducted propensity-score matching to match statin-exposed patients with those unexposed. Afterwards, we assessed the effect of statin exposure on the risk of heart failure-related hospitalizations or emergency visits by estimating both relative and absolute effects. Collectively, we provided a general methodological framework to assess treatment effect in incomplete observational data. In addition, we presented a practical approach to produce overall cumulative incidence function (CIF) based on estimates from multiple imputed and PS-matched samples.

• 한국조사연구학회지:조사연구
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• 제10권1호
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• pp.169-186
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• 2009

본 연구는 사회조사에서 무응답으로 인한 편향을 축소하는 방안으로 성향점수를 이용하는 방법과 사례를 설명하기 위해서 성향점수 방법의 이론적인 개념과 배경을 정리하였다. 또한 성향점수 방법을 처음으로 적용한 역학적인 관찰연구에서 성향점수 모형의 정의와 이론적 배경을 살펴보았고 추정에서 편향의 축소방법으로 이용되는 가지 성향점수 방법을 정리하였다. 성향점수로 짝짓기는 통제그룹의 데이터가 상대적으로 많을 경우에 이용되고 부차분류법은 통제그룹의 모든 데이터를 이용할 수 있으며 회귀모형을 이용한 보정은 다중공변량에서도 사용할 수 있을 뿐만 아니라 각 관찰단위에 성향점수 값을 산출하여 사용할 수 있는 특징이 있다. 그리고 사회여론조사에서 항목무응답으로 인한 편향을 축소하는 데 성향점수 가중법을 적용하는 절차를 제안하고 기존의 데이터를 이용하여 실제 적용에 대한 가능성을 검토하였다.

• 사상체질의학회지
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• 제28권1호
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• pp.11-18
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• 2016

Objectives The body shape was a key information for diagnosing the Sasang constitution (SC) in Sasang constitutional medicine. The aim of this study was to compare the body shapes and mainly focusing on the Korean and Chinese-KoreanMethods We calculated the propensity score for each SC type in males and females separately, and compared body shape including 8 circumference and 5 width between Korean and Chinese-Korean according to the sex and SC.Results Koreans have larger trunk and hip area compared to Chinese-Koreans, while Chinese-Koreans have larger abdomen compared with Koreans. Most variables were significantly different among SC types, for both Korean and Chinese-Korean. Especially, the Taeumin (TE) type has the largest body shape compared with the other SC types, it was similar between Korean and Chinese-Korean.Conclusions This study showed that the TE type has the largest body shape, followed by Soyangin (SY) and Soeumin (SE) in order, for both Korean and Chinese-Korean respectively. These results suggests that the body shape of Chinese-Korean is similar with Korean based on SC type.

• Journal of the Korean Data and Information Science Society
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• 제27권1호
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• pp.91-100
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• 2016

성향점수 매칭이란 선택편의가 존재 할 수 있는 두 집단의 데이터를 성향 점수로 매칭하여 비슷한 성향을 갖는 데이터를 추출하는 방법이다. 본 논문은 그 중 하나인 퍼지 매칭 방법을 제시하였다. 성향 점수를 만들기 위해 통제변수를 선정하는 방법과 로지스틱 회귀분석을 통하여 성향 점수를 구하는 방법을 제시하였으며, 이 점수로 퍼지 매칭을 통해 성향이 비슷한 실험 집단과 통제 집단을 추출할 수 있었다. 본 논문에서는 허용오차 범위를 달리하여 분포도와 표준화 차이를 통해 두 집단이 동일한 집단임을 증명했으며, 허용오차 범위 점수가 작아질수록 선택되어 지는 케이스 수도 작아지는 것을 확인 할 수 있었다.

• 대한간호학회지
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• 제37권3호
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• pp.414-421
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• 2007

Background: Nursing intervention studies often suffer from a selection bias introduced by failure of random assignment. Evaluation with selection bias could under or over-estimate any intervention's effects. PS matching (PSM) can reduce a selection bias through matching similar Propensity Scores (PS). PS is defined as the conditional probability of being treated given the individual's covariates and it can be reused to balance the covariates of two groups. Purpose: This study was done to assess the significance of PSM as an alternative evaluation method of nursing interventions. Method: An intervention study for patients with some baseline individual characteristic differences between two groups was used for this demonstration. The result of a t-test with PSM was compared with a t-test without matching. Results: The level of HbA1c at 12 months after baseline was different between the two groups in terms of matching or not. Conclusion: This study demonstrated the effects of a quasi-random assignment. Evaluation using PSM can reduce a selection bias impact that affects the result of the nursing intervention. Analyzing nursing research more objectively to reduce selection bias using PSM is needed.