• Journal of the Korean Data and Information Science Society
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• 제15권2호
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• pp.431-439
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• 2004

In this paper, we present an effective method for process control using the Demerit-EWMA control chart in the process where nonconforming units or nonconformities are occurred by various types. We compare performance of Demerit control chart, Demerit-CUSUM control chart and Demerit-EWMA control chart based on the average run length(ARL).

• Communications for Statistical Applications and Methods
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• 제13권2호
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• pp.219-231
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• 2006

When the correlation of two random variables is weak, the value of one variable can not be used effectively to predict the other. Even when most of the values are overlapped, it is difficult to find a linear relationship. In this paper, we propose two graphical methods of representing the measures of correlation and independence between two random variables. The first method is used to represent their degree of correlation, and the other is used to represent their independence. Both of these methods are based on the cumulative distribution functions defined in this work.

• Journal of the Korean Data and Information Science Society
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• 제6권1호
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• pp.31-37
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• 1995

We consider density estimates of the usual type generated by a kernel function. By using the limit theorems for the maximum of normalized deviation of the estimate from its expected value, we propose to use data dependent bandwidth in the tests of goodness of fit based on these statistics. Also a small sample Monte Carlo simulation is conducted and proposed method is compared with Kolmogorov-Smirnov test.

• Journal of the Korean Data and Information Science Society
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• 제18권3호
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• pp.817-826
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• 2007

In this paper, we derive the approximate maximum likelihood estimators of the scale parameter and the location parameter in a generalized extreme value distribution under multiply Type-II censoring by the approximate maximum likelihood estimation method. We compare the proposed estimators in the sense of the mean squared error for various censored samples.

• Communications for Statistical Applications and Methods
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• 제6권3호
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• pp.901-908
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• 1999

Using the Transformed Lorenz curve which is introduced by Cho et al.(1999) we propose the test statistic for testing of normality that is very important test in statistical analysis and compare the proposed test statistic with the Shapiro and Wilk's W test statistic in terms of the power of test through by Monte Carlo method.

• Journal of the Korean Statistical Society
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• 제32권3호
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• pp.225-233
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• 2003

In this paper we make use of the parity check matrices of the codes based on inverting construction $Y_1$ to construct a number of new asymmetric orthogonal arrays with higher strength and higher number of levels using the method of construction of asymmetric orthogonal arrays given by Suen et al. (2001).

• Journal of the Korean Statistical Society
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• 제31권3호
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• pp.343-357
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• 2002

This paper proposes a method for producing smooth and positive estimates of the intensity function of an inhomogeneous Poisson process based on the shrinkage of wavelet coefficients of the observed counts. The information projection is used in conjunction with the level-dependent thresholds to yield smooth and positive estimates. This work is motivated by and demonstrated within the context of a problem involving gamma-ray burst data in astronomy. Simulation results are also presented in order to show the performance of the information projection estimators.

• 한국음향학회지
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• 제33권1호
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• pp.81-86
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• 2014

본 논문은 음악신호의 옥타브 밴드 상에서 주파수와 시간 방향의 순서 통계량에 기반한 음악분류기에 대한 연구이다. 음악의 화음 및 강약 구조를 표현하기 위해서 파워스펙트럼의 옥타브 밴드 순서 통계량을 이용하였다. 널리 사용되고 있는 두 음악 데이터셋을 이용한 성능 실험을 통해서, 옥타브 밴드 순서 통계량이 기존의 MFCC 와 옥타브밴드 스펙트럼 고저차 특징에 비해서 두 데이터셋에대해 각각 2.61 %와 8.9 % 장르 분류정확도가 개선되었다. 실험결과는 옥타브 밴드 순서 통계량이 음악 장르 분류에 적합함을 보인다.

• 응용통계연구
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• 제15권1호
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• pp.153-163
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• 2002

현재 우리나라 경영대학에서 이루어지고 있는 통계학교육은 약간의 문제점을 가지고 있다. 그 중에서도 피교육자들인 학생들이 가지고 있는 수학에 대한 거부반응은 통계학이 보급되는 과정에서 커다란 걸림돌로 작용을 한다. 그러나 경영활동의 의사결정은 미래에 발생하는 수많은 변수와 불확실성을 포함한 채 현재 시점에서 이루어지는 특성이 있기 때문에 통계학의 필요성은 날이 갈수록 증대되고 있는 실정이다. 본 논문에서는 통계학이 경영학과 접목되어 바람직한 방향으로 나가기 위한 몇 가지 방안을 제시하고자 한다. 특히 경영통계의 효과적인 교육을 위해 스프레드쉬트에서의 시뮬레이션이 어떻게 이용될 수 있는지 예제를 통하여 알아보기로 한다.

• Journal of the Korean Data and Information Science Society
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• 제15권4호
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• pp.707-716
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• 2004

Recently, many areas of application such as statistics and industrial engineering are interested in the effective education of databases. In this article we design and implement a database learning system based on learner management techniques. The system supports a personalized/ team-centered learning environment, monitoring the learning attitude of learners, and a method for the assessment.