• The Korean Journal of Applied Statistics
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• v.2 no.2
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• pp.79-89
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• 1989

Modified Pearson $X^2$ statistic is concerned. Moreover the four statistics(Pearson, Wald, modified sample design effects and reduction factor) are compared in one-stage sampling situation. In case of categorical of fit and independence tests for sample data above, it is shown that there is a significant behavior between Pearson $X^2$ and Wald statistic, but minor difference in modified statistics by simulation methods.

• The Korean Journal of Applied Statistics
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• v.19 no.2
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• pp.361-368
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• 2006

There are lots of two and three dimensional graph representing two dimensional categorical data. Among them, Li, et al. (2003) proposed Diamond Graph that projects three dimensional graph into two dimension whereby the third dimension is replaced with a diamond shape whose area and middle and vertical and horizontal lengths represent the outcome. In this paper, we use the Diamond graph to test the independence of two predictor variables for two dimensional data. And this graph could be applied for finding the best fitted log-linear model to three dimensional data.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.786-791
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• 2005

경향성을 분석하기 위한 여러 기법 가운데 비모수적 방법인 Mann-Kendall 검정(MK 검정)은 수문시계열의 분석에서 널리 사용되어지고 있다. 이 검정 방법은 분석 대상 자료가 독립이라는 가정 하에 수행되며, 자료가 계열상관되어 있는 경우에는 그 상관성의 영향으로 경향성 존재의 유무를 정확하게 판단할 수 없게 된다. 따라서 MK 검정을 이용할 때 자료의 상관성으로 인해 받게되는 영향을 소거시키기 위해 효과적인 자료의 크기(Effective Sample Size, ESS)를 이용하는 수정된 MK 검정 방법을 이용하고자 한다. 본 연구에서는 ESS가 얼마만큼 계열상관성을 제거할 수 있는지 Monte Carlo모의를 통해 검토하였다. MK 검정 결과 계열상관계수의 증가에 따라 자료가 경향성을 나타내는 비율이 높아 겼으나, ESS에 의해 수정된 MK 검정을 수행한 결과 계열상관계수의 영향이 제거되었음을 알 수 있었다. 그러나 ESS에 치한 방법은 상관성의 영향을 과대하게 제거하게 되고, 이에 의해 실제 경향성이 존재하는 자료마저도 비 경향성이라고 판단하게 되는 오류를 가지고 있었다. 이러한 문제점을 해결하기 위해 MK 검정에서 경향성으로 판단된 자료에 대해 경향정도를 분석하여 제거한 후 다시 ESS에 의해 수정된 MK 검정을 실시하였다. 본 연구를 통하여 상관성이 존재하는 자료에 대한 MK 검정 방법의 오류를 제거 할 수 있었으며, 또한 실측 자료의 적용을 통해 수정 MK 검정이 경향성 분석에 매우 유용함을 확인 하였다.

• Journal of the Korean GEO-environmental Society
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• v.24 no.12
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• pp.61-67
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• 2023

Heat pipes located underground in urban areas and operated under high temperature and pressure conditions can cause large-scale human and economic damage if damaged. In order to predict damage in advance, damage and construction information of heat pipe are analyzed to derive independent variables that have a correlation with frequency of damage, and a simple regression analysis modified model using each variable is applied to the field. However, as the correlation between independent variables applied to the model increases, the independence between variables is harmed and the reliability of the model decreases. In this study, the independence of the pipe diameter, burial depth, insulation level of monitoring system, and disconnection or short circuit of the detection line, which are judged to be interrelated, was tested to derive a method for combining variables and setting categories necessary to apply to the frequency of damage estimation model. For the test of independence, the continuous variables pipe diameter and burial depth were each converted into three categories, insulation level of monitoring system was converted into two categories, and the categorical variable disconnection or short circuit of the detection line status was kept as two categories. As a result of the test of independence, p-value between pipe diameter and burial depth, level of monitoring system and disconnection or short circuit of the detection line was lower than the significance level (α = 0.05), indicating a large correlation between them. Therefore, the pipe diameter and burial depth were combined into one variable, and the categories of the combined variable were set to 9 considering the previously set categories. The insulation level of monitoring system and the disconnection or short circuit of the detection line were also combined into one variable. Since the insulation level is unreliable when the detection line status is disconnection or short circuit, the categories of the combined variable were set to 3.

• The Korean Journal of Applied Statistics
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• v.20 no.2
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• pp.323-332
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• 2007

We present a new type of portmanteau test in the frequency domain which is derived from the discrete cosine transform(DCT). For the stationary time series, DCT coefficients are asymptotically independent and their variances are expressed by linear combinations of autocovariances. The covariance matrix of DCT coefficients for white noises is diagonal matrix whose diagonal elements is the variance of time series. A simple way to test the independence of time series is that we divide DCT coefficients into two or three parts and then compare sample variances. We also do this by testing the slope in the linear regression model of which the response variables are absolute values or squares of coefficients. Simulation results show that the proposed tests has much higher powers than Ljung-Box test in most cases of our experiments.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.333-342
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• 2020

The purpose of this study is to identify the mediating effects of family function in the relationship between depression and health promotion behavior among university students. Data were collected from December 1 to December 31, 2018 and the participants included 340 university students, who responded to the question regarding health promotion behavior, family function and depression. The data were analyzed by descriptive statistics, t-test, ANOVA, Spearman's correlation coefficients, and multiple regression, mediation regression analysis of Baron and Kenny using the SPSS/WIN 23.0 program. As a result, A negative correlation is found between health promotion behavior and depression (r=-.48, p<.001), and positive correlation is among family function (r=33, p<.001), negative correlation is found between depression and family function (r=-.45, p<.001). family function have a partial mediating effect on the relationship between depression and health promotion behavior (Sobel test: -2.53, p<.05). Results of this study suggest that it is important to manage family function to improve health promotion behavior caused by depression.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.365-368
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• 2012

어의 중의성 해소는 자연어처리에서 중요한 역할을 한다. 감독 중의성 해소 방법은 비감독 중의성 해소 방법보다 높은 성능을 나타내지만, 구축비용이 큰 대규모 의미부착 말뭉치가 필요하다. 본 논문에서는 중국어 어휘의미망(HowNet)과 의미 미부착 말뭉치를 이용한 중국어 비감독 어의 중의성 해소 방법을 제안한다. 의미 미부착 말뭉치에서 통계정보를 추출하고, 중국어 어휘 의미망에서 중의성 어휘의 의미별 형제어를 추출하여 중의성 어휘의 주변 문맥에 나타나는 어휘와 카이제곱검정(${\chi}^2$-test)에 의한 독립성 검정을 통해 어휘 간 연관성을 판단하고 중의성 해소를 한다. 본 논문에서 제안한 중의성 해소방법의 성능을 SemEval-2007 평가데이터에서 측정한 결과 명사와 동사에서 각각 64.7%, 49.4%를 나타냈다. 이는 SemEval-2007 중국어 비감독 중의성 해소에서 가장 높은 성능을 나타낸 시스템보다 13.1%, 13.9% 높은 성능이다.

• Journal of the Korean Data and Information Science Society
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• v.9 no.2
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• pp.237-246
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• 1998

We put the pseudo-random number generator into catagories like MiCG, MuCG, URG, ICG, EICG, and test uniformity and independency by 10,000 times through n empirical trial after selecting this random number generator. Here, from a fraction of data(20, 40, 60, 80, 100) with a significance level of 0.1, 0.05 and 0.01, we drive cumulative frequency with K-S, $X^{2}$, poker, run, autocorrelation test. As a result from the uniformity and independency among five random number generators based on all these data, all random number generator except EICG passed uniformity and independency test, and the URG turn out to be excellent in periodicity.

• Korean Management Science Review
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• v.6 no.2
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• pp.27-49
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• 1989

본 논문은 우리나라 제조기업의 하청생산 관계에 있어서 구매와 생산시스템에 관한 연구를 대기업의 부품구입 구매과업과 중소기업의 생산과업을 각각 원가절감, 품질행상, 납기준수라 설정하고 이를 연구한 것이다. 세가지 생산과업 중 상대적으로 더 강조하는 기업을 원가절감 전략그룹, 품질향상 전략그룹, 납기준수 전략그룹이라 명명하고, 연구내용은 첫째 중소기업 생산과업과 대기업 구매과업과의 결합도를 분석하였다. 둘째 대기업의 중소기업에 대한 지원성과의 차이를, 세째 과업그룹간의 과업의 성과차이를 분석하였다. 이를 실증적으로 분석하기 위하여 서베이 조사방법을 이용하였는데, 연구대상 기업은 국내의 자동차, 전자.통신, 중장비.기계.조선업종의 세트조립 대기업에 부품과 원료를 공급하는 수급기업체 협의회 회원 중소기업으로 하였다. 중소기업의 업종은 금속, 기계, 장비 제조 및 화학, 석탄, 고무 및 프라스틱 제조인 등록 및 일반 법인이었고, 전국에서 112개 중소기업이 표본으로 추출되어 분석되었다. 연구가설들은 통계 패키지를 이용한 독립성 검정, 요인분석, 분산분석, 비모수 검정방법을 통하여 검정되었다.

• Journal of the Korean Data and Information Science Society
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• v.10 no.1
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• pp.37-45
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• 1999

In this paper, we consider two components system having Marshall-Olkin's bivariate exponential model. For the bivariate random censorship, we obtain maximum likelihood estimators of parameters and system reliability. And we propose the methods of homogeniety and independence tests using asymptotic normality. Also we compute the estimators and p-values of the testings through Monte Carlo simulation.