• 응용통계연구
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• 제27권2호
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• pp.227-237
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• 2014

우리는 회귀분석에서 설명변수들 중 일부가 질적 변수인 경우 지시변수를 사용한다. 또한 공분산분석모형에서는 관심인자의 효과에 대한 유의성 검정시 연속변수인 공변수로 주어지는 방해인자를 미리 회귀분석으로 제거한다. 지시변수 사용 회귀모형이나 공분산분석모형을 위한 확증적 자료분석 전에 탐색적 자료분석의 한 수단으로서 자료깊이에 근거한 DD-plot을 이용하면 집단 간의 차이를 쉽게 알아볼 수 있다. 이 방법은 오차항의 통계모형을 가정하지 않으므로 유용한 탐색적 방법이 될 수 있다. 몇 가지 사례들을 통하여 DD-plot이 지시변수 사용 회귀모형이나 공분산분석모형을 위한 그래픽 탐색적 자료분석방법으로서 유용함을 보였다.

• 한국분무공학회지
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• 제18권2호
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• pp.81-86
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• 2013

To comply with the regulation of the reinforcing Clean Air Conservation Act, it is necessary for the semiconductor manufacturers to develop effective low-concentration acid gas abatement system to treat the flue gas. The low-concentration acid gas was found to be harder to deal with than the high-concentration one. In this study, the effect of various potential treatments such as air-assist nozzle spraying, magnetizing the scrubbing water, and adding surfactants to spraying and scrubbing water were investigate through the application of the statistical ANCOVA method, which was proved to be very useful tool when the inlet concentration of acid gas could not be controlled precisely and it affected the removal efficiency of the abatement system.

• 기본간호학회지
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• 제19권2호
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• pp.168-178
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• 2012

Purpose: The purpose of this study was to compare self-care behavior, diabetes-related stress and stress coping style among 3 blood glucose control groups (good, inadequate, and poor blood glucose control groups). Methods: Participants were 102 type 2 diabetic patients (good group: 41, inadequate group: 31, poor group: 30). Data were collected from Feb 19 to Mar 24, 2010 and were analyzed using Chi-square, Fisher's exact test and ANCOVA with SPSS/WIN 12.0. Results: Using ANCOVA with frequency of admission, and illness duration as covariates, significant differences were found among the 3 groups in self-care behavior (total score) and the exercise subscale. Using ANCOVA significant differences were found among 3 groups in diabetes-related stress (total score), emotional burden subscale and regimen distress subscale. Using ANCOVA no difference in stress coping was found among the 3 groups, but there was a significant difference in the problem-oriented coping subscale. Conclusions: Self-care behavior, diabetes-related stress, and stress coping style are factors influencing blood glucose control. The results of this study suggest that for improving blood glucose control, self care education program focused on diet and exercise in addition to stress management program for promoting problem oriented coping capability are recommended.

• 대한화장품학회지
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• 제39권2호
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• pp.105-115
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• 2013

국내의 주름개선 혹은 미백 효능을 평가하기 위한 인체시험 방법은 식약청 가이드라인에 근거하여 시행 되어왔으며, 인체시험에서 육안평가 및 기기평가 결과에 대해 시험군과 대조군 간의 효과를 비교하기 위해서 unpaired t-test를 주로 이용하였고, 시술 전후의 효과를 비교하기 위해서 paired t-test를 이용하였다. 설문평가 결과에 대해서는 빈도분석을 이용한 기술통계법이 이용되고 있다. 미국 및 유럽의 임상 평가기관에서도 이와 유사한 시험법 및 통계분석 방법을 이용하고 있다. 그러나 동일 개체에 대하여 처치를 반복 적용하여 얻은 자료는 서로 관련성이 높아 이를 감안한 분석법을 적용해야 한다. 따라서 본 연구에서는 화장품 분야에서는 처음으로 기능성 화장품 중 주름 개선 및 미백 효능 시험의 육안평가 및 기기평가 자료에 대해 repeated measures ANCOVA (RM ANCOVA)와 repeated measures ANOVA (RM ANOVA)를 적용하여 통계 방법의 타당성 여부를 검증함으로서 현재의 인체시험 방법에 적합한 새로운 통계분석 방법을 제시하였다.

• Communications for Statistical Applications and Methods
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• 제19권5호
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• pp.721-729
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• 2012

Various methods control the influence of a covariate on a response variable. These methods are analysis of covariance(ANCOVA), RANK ANCOVA, ANOVA of (covariate-adjusted) residuals, and Kruskal-Wallis tests on residuals. Covariate-adjusted residuals are obtained from the overall regression line fit to the entire data set that ignore the treatment levels or factors. It is demonstrated that the methods on covariate-adjusted residuals are only appropriate when the regression lines are parallel and covariate means are equal for all treatments. In this paper, we proposed the new nonparametric method on the ANCOVA model, as applying joint placement in a one-way layout on residuals as described in Chung and Kim (2007). A Monte Carlo simulation study is adapted to compare the power of the proposed procedure with those of the previous procedure.

• 한국데이터정보과학회:학술대회논문집
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• 한국데이터정보과학회 2006년도 PROCEEDINGS OF JOINT CONFERENCEOF KDISS AND KDAS
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• pp.171-179
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• 2006

For the problem of variable selection in linear models, we consider the errors are correlated with V covariance matrix. Hocking's theorems on the effects of the overfitting and the underfitting in linear model are extended to the less than full rank and correlated error model, and to the ANCOVA model.

• 한국산학기술학회논문지
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• 제15권3호
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• pp.1396-1403
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• 2014

이 연구는 학습역량 관련 지식, 창의성, 동기로 구성된 Hope프로그램이 대학생의 창의성, 문제해결, 학습동기, 학습행동에 미치는 영향을 규명하고자 시도되었다. 연구대상자들은 총 49명이었으며 Hope프로그램은 8월 26일부터 9월 13일까지 3주 동안 14시간에 걸쳐 운영되었다. 사전 사후 검사를 거쳐 실험집단과 대조집단에게 창의성, 문제해결, 학습동기, 학습행동을 검사하였다. 사전검사에서 두 집단의 동질성이 확보되지 않아, 실험 후 공분산분석(ANCOVA)을 실시하였으며, 그 결과 Hope프로그램을 실시한 실험집단과 대조집단은 창의성, 문제해결, 학습동기, 학습행동 점수에서 유의한 차이를 나타내었다(p<.05).

• Restorative Dentistry and Endodontics
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• 제43권4호
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• pp.43.1-43.7
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• 2018

• Journal of applied mathematics & informatics
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• 제32권3_4호
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• pp.343-357
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• 2014

In many non-life insurance applications past data are given in a form known as the run-off triangle. Smoothing such data using parametric crisp regression models has long served as the basis of estimating future claim amounts and the reserves set aside to protect the insurer from future losses. In this article a fuzzy counterpart of the Hoerl curve, a well-known claim reserving regression model, is proposed to analyze the past claim data and to determine the reserves. The fuzzy Hoerl curve is more flexible and general than the one considered in the previous fuzzy literature in that it includes a categorical variable with multiple explanatory variables, which requires the development of the fuzzy analysis of covariance, or fuzzy ANCOVA. Using an actual insurance run-off claim data we show that the suggested fuzzy Hoerl curve based on the fuzzy ANCOVA gives reasonable claim reserves without stringent assumptions needed for the traditional regression approach in claim reserving.

• 한국조리학회지
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• 제13권4호
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• pp.57-66
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• 2007

The purpose of this study was to assess the effects of service quality, perceived sacrifice, food price and image on value. A total of 273 questionnaires were completed. MANOVA, ANOVA, and ANCOVA were used to measure the main effects and mediating effects of service quality and perceived sacrifice on the relationships among price, image, and value. The main effects of price on service quality, perceived sacrifice, and value were statistically significant. The main effects of image on service quality and value were statistically significant. As expected, when price, service quality, and perceived sacrifice regressed on the value, they were statistically significant. Moreover, when image, service quality, and perceived sacrifice regressed on the value, they had statistically significant effects on value. The results demonstrated that service quality played a mediating role in the relationship between price and value.