• Communications for Statistical Applications and Methods
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• v.2 no.2
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• pp.33-42
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• 1995

종속 관측중단(dependent censoring)이 카이제곱 형태의 적합도 검정에 어떻게 영향을 미치고 종속도와 관측중단된 정도에 따라 검정의 오류와 검정력이 변화하는 형태를 시뮬레이션을 통해 경험적으로 알아보았다. Sakar(1987)가 제안한 이변량 지수분포로부터 종속 관측중단된 자료를 만들어 Kim(1993)이 제안한 방법과 Akritas(1988)가 제안한 적합도의 검정방법을 적용하였다. 전체적으로 Kim(1993)의 검정법이 더 효과적이었으며 관측 중단된 정도가 클 때는 중속도에 따라 검정의 오류와 검정력이 무척 크게 변하였다.

• The Korean Journal of Applied Statistics
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• v.17 no.2
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• pp.337-346
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• 2004

The Pearson chi-square goodness-of-fit test and the likelihood ratio tests are usually used for testing independence in two-way contingency tables under random sampling. But both of these tests may provide false results for the contingency table with clustered observations. In this case we consider the generalized linear mixed model which includes random effects of clustering in addition to the fixed effects of covariates. Both the heterogeneity between clusters and the dependency within a cluster can be explained via generalized linear mixed model. In this paper we introduce several types of generalized linear mixed model for testing independence in contingency tables with clustered observations. We also discuss the fitting of these models through a real dataset.

• Journal of Korean Society of Transportation
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• v.28 no.3
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• pp.19-28
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• 2010

Almost domestic cycleways have been established without characteristic of land uses. These cycleways can always not provide optimal condition for safety and convenience not to speak of efficiency. This research having a purpose to accomplish more safety and convenience has tried to classify cycleways detail and to analyze cycleways types by land uses. It verified the difference among the characteristic of traffic on the land uses using the Chi-square test, and found the land use that had the strongest characteristic. Finally, it has proposed the suitable cycleway types to land uses.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.102-102
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• 2023

벤포드 법칙(Benford's Law)은 실생활에서 관찰되는 수치 데이터를 첫 자리 숫자에 따라 분류할 때 첫 자리의 숫자가 커질수록 그 분포가 점차 감소되는 현상을 말한다. 이러한 벤포드 법칙은 일반식으로 도출하여 다양한 자릿수로 확장하여 적용할 수 있는 연구결과가 제시되었으며, 회계학, 사회과학, 물리학, 컴퓨터과학, 생물학 등 다방면의 수치 자료에서 그 유효성이 확인되고 있다. 자릿수의 관찰빈도를 분석하는 것만으로 많은 양의 실생활 데이터에서 빠르고 쉽게 데이터 조작여부를 탐지하거나 1차적인 데이터 품질검사에 효과적으로 활용되고 있다. 본 연구에서는 다학제적 연구의 측면에서 수학·물리적 법칙인 벤포드 법칙을 일유량 등 다양한 수문학 측정자료에 적용하여 그 적용가능성을 확인하고 자료의 불균질성과 신뢰성을 빠르게 탐지할 수 있는 방법론을 제시하고자 한다. 수문자료는 공인심의를 통해 자료의 신뢰도를 확보하고 있으나 확정·배포까지 약 2년이 소요되어 활용기간 단축에 대한 사용자 요구가 지속되고 있는 실정이다. 따라서 본 연구에서는 분석대상 데이터의 자릿수 관찰빈도가 벤포드 법칙에 의한 예상자릿수 빈도를 따르는지 여부에 대한 가설을 설정하고 카이제곱 검정 또는 Kolmogorov-Smirnov(K-S) 검정 등을 통해 적합도에 대한 통계적 유의미함을 분석함으로써 대략적으로나마 빠르고 쉽게 측정자료의 신뢰성을 판단할 수 있다. 본 연구는 다양한 학문과의 결합을 통한 새로운 접근을 시도함으로써 빅데이터 시대에 효과적으로 수자원의 개발, 관리 및 운영의 의사결정을 하는데 도움이 될 수 있을 것으로 판단된다.

• Journal of East-West Nursing Research
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• v.14 no.1
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• pp.78-86
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• 2008

본 연구는 여대생의 건강증진행위를 설명하기 위하여, 문헌고찰을 통해 가설적 모형을 도출하고, 여대생을 대상으로 건강증진행위를 횡단적으로 조사하여 모형의 적합성과 모형에서 제시된 가설을 검증하는 서술적 상관관계 연구이다. 연구에 사용된 변수는 건강증진행위와 관련된 선행 문헌의 고찰을 근거로 선정되었으며, 총 280명의 자료가 최종 분석에 이용되었다. 설문지는 Pender의 건강증진모형을 기초로 하여 개발하였으며, 조정요인 5문항, 건강상태 지각 3문항, 건강 통제위 4문항, 자아 존중감 5문항, 건강증진 행위 24문항의 총 41문항으로 구성하여 사용하였다. 개발된 항목에 대하여 간호대학생들을 대상으로 사전 조사를 실시하여 최종적인 설문지를 완성하였다. 본 연구모형에 대한 구성개념의 파악을 위해서 탐색적 요인분석을 실시하였고, 측정항목에 대한 요인별 단일 차원성 확인 및 통계적 검정을 위해 확인적 요인분석을 실시하였다. 연구의 가설검증을 위해 공변량 구조분석을 실시하였다. 모형의 적합도는 카이제곱은 244.04(자유도=121, p<0.001), GFI=0.91, CFI=0.97, NNFI=0.96, RMSR= 0.022으로 나타났다. 분석결과 여대생의 자아존중감과 내적통제위는 건강상태지각 및 건강증진행위에 유의한 영향을 미치는 요인으로 확인되었으며, 여대생의 건강상태지각은 건강증진행위에 유의한 영향을 미치는 것으로 나타났다.

• Journal of the Korean Data and Information Science Society
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• v.20 no.1
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• pp.1-9
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• 2009

Let us consider that the variance function in regression model has a discontinuity/change point at unknown location. Yu and Jones (2004) proposed the local polynomial fit to estimate the log-variance function which break the positivity of the variance. Using the local polynomial fit, Huh (2008) estimate the discontinuity point of the log-variance function. We propose a test for the existence of a discontinuity point in the log-variance function with the estimated jump size in Huh (2008). The proposed method is based on the asymptotic distribution of the estimated jump size. Numerical works demonstrate the performance of the method.

• Journal of the Korean Data and Information Science Society
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• v.25 no.6
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• pp.1231-1239
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• 2014

In this paper we analyse the distributions of the number of goals scored by home teams and away teams in K-league soccer outcomes between 1983 and 2012. Real soccer data is explained in K-league using statistical distributions such that Poisson, negative binomial, extreme value and zero inflated Poisson. How close the goals of home and away fits the different distributions are tested by performing chi-square goodness of fit tests. According to these tests, the Poisson distribution gives the best fit to the home goals data. But it is best to model the away goals data on zero inflated Poisson distribution. Also, there is some weak evidence of the dependence for home and away goals.

• Management & Information Systems Review
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• v.31 no.1
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• pp.1-21
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• 2012

This study analyzes empirically the effect of the degree of interest in cultural marketing on corporate image and how the corporate images affect on consumers' clothes purchasing behavior through the case of a fashion brand, 'Uniqlo'. For this, Chi-square test and independent sample T-test were used for the verification of differences in frequency and average by general characteristics of respondents. To observe the effects between ration scales, it carried out a multiple regression analysis, and also, using AMOS16.0, it verified the suitability of the route model and estimated the coefficients for each route. From the result of analysis, it was found that degree of consumer's interest in cultural marketing affects on corporate images such as corporate confidence and marketing and the corporate image again is closely related to consumer's clothes purchasing behavior and satisfaction. In other words, the consumers who have greater interest in corporations using cultural marketing or who had participated in various cultural events are more likely to think that 'Uniqlo' is a reliable corporation who actively uses cultural factors in marketing. Likely, it was observed that the positive corporate image of 'Uniqlo' has a large influence on purchase of their products and also, it makes consumers feel as if they are participating in mecenat, thus increasing consumer's satisfaction after purchase. This study has a limitation in generalization of study result because it focused on a case of particular brand. However, it is still helpful for the empirical study for growth and reinvigoration of the market for cultural marketing, and through a case of leading corporation, it provides implications to the corporations who use or do not use cultural marketing.

• Journal of Korean Society of Transportation
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• v.24 no.6 s.92
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• pp.33-43
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• 2006

This research is to the selection of optimal probability distribution as well as the estimation for design hourly factor in consideration of traffic characteristic, such as road function, lane number and AADT. To accomplish the objectives, we are applied to various probability distribution using traffic data that observed at permanent traffic count points in 2005. The parameters or the selected 14 probability distribution were estimated based on the method of maximum likelihood and the validity condition of the estimated parameter The goodness-of-fit test, such as chi-square test. was performed as well as the estimation of design hourly factor. As a result, An appropriate distributions of each case were selected : Pearson V for two lane of rural roads, LogLogistic for the four lane of rural roads, LogLogistic for the urban roads, Extreme value for recreation roads. And optimal K factor are as following : $0.1{\sim}0.2 $ for two lane of rural roads, $0.09{\sim}0.14$ for the four lane of rural roads. $0.07{\sim}0.13$ for the urban roads, $0.1{\sim}0.2$ for recreation roads.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.10
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• pp.1277-1286
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• 2018

In this paper, we provide flexible scalability of computing resources in cloud environment and Apache Hadoop based cloud environment for analysis of public medical information big data. In fact, it includes the ability to quickly and flexibly extend storage, memory, and other resources in a situation where log data accumulates or grows over time. In addition, when real-time analysis of accumulated unstructured log data is required, the system adopts Hadoop-based analysis module to overcome the processing limit of existing analysis tools. Therefore, it provides a function to perform parallel distributed processing of a large amount of log data quickly and reliably. Perform frequency analysis and chi-square test for big data analysis. In addition, multivariate logistic regression analysis of significance level 0.05 and multivariate logistic regression analysis of meaningful variables (p<0.05) were performed. Multivariate logistic regression analysis was performed for each model 3.