• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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• pp.1093-1098
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• 1995

IAEA(International Atomic Energy Agency, 국제원자력기구)에서는 사찰활동 수행시, 비복원추출(sampling without replacement)을 기술하는 초기하분포 대신 복원추출(sampling with replacement)을 기술하는 이항분포를 사용하여 표본크기를 계산하여 사찰방법들에 할당한다. 본 연구에서는 이항근사법이 사용되는 IAEA의 표본크기 할당계산결과와 이항근사법 대신 초기하분포를 적용한 IAEA표본크기 할당계산결과를 비교 검토하였다.

• Communications for Statistical Applications and Methods
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• 제3권3호
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• pp.161-168
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• 1996

This paper describes a sampling method, which can be used instead of the simple random sampling without replacement(SRSWOR). This method, circular sampling, assumes that the sampling units of the population are arranged in circular format, and randomly selects as many as samples of contiguous units. Therefore this method gathers information quicker and easier than STSWOR. In certain circumstances, the reliability of this method is better than that of STSWOR. And of circular sampling would be applied to nonprobability could be determined. methods, the reliability of the sample results in terms of probability could be determined.

• Journal of the Korean Statistical Society
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• 제27권4호
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• pp.459-469
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• 1998

Balanced half sample method is a simple variance estimation method for complex sampling designs. Since it is simple and flexible, it has been widely used in large scale sample surveys. However, the usual BHS method overestimate the true variance in without replacement sampling and two-stage cluster sampling. Focusing on this point , we proposed an unbiased BHS variance estimator in a stratified two-stage cluster sampling and then described an implementation method of the proposed estimator. Finally, partially BHS design is explained as a tool of reducing the number of replications of the proposed estimator.

• Journal of the Korean Data and Information Science Society
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• 제21권3호
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• pp.481-491
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• 2010

수강하는 학생 개개인이 응답한 여러 개의 파일을 한 파일에 모은 다음 이 자료를 가지고 난수생성, 표본추출 과정과 방법, 모수와 통계량을 비교하는 프로그램을 엑셀 매크로로 작성하였다. 모집단에서 일부분의 표본을 추출하여 모수와 통계량의 차이를 비교하는 등 자료의 생성, 분석, 결과의 해석을 빠른 시간내에 해결하여 학생들이 흥미를 가지고 수업에 참여하도록 유도한다. 엑셀에서는 난수발생시 중복된 값이 발생하는데 본 연구에서는 비주얼베이직 매크로로 비복원추출 프로그램을 작성하여 활용한다.

• Journal of the Korean Data and Information Science Society
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• 제13권2호
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• pp.147-156
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• 2002

In this paper, we propose EWMA control charts using the life time data for the system with the constant failure rate, which were drawn from the fixed sampling interval without replacement(with replacement), and investigate the power of detection of EWMA by comparing ARL of EWMA control charts with one of Shewhart control charts.

• 한국데이터정보과학회:학술대회논문집
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• 한국데이터정보과학회 2002년도 춘계학술대회
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• pp.141-149
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• 2002

In this paper, we propose EWMA control charts using the life time data for the system with the constant failure rate, which were drawn from the fixed sampling interval without replacement (with replacement), and investigate the power of detection of EWMA by comparing ARL of EWMA control charts with one of Shewhart control charts.

• Communications for Statistical Applications and Methods
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• 제11권2호
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• pp.413-418
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• 2004

Statistically illiterate people seem to believe that there are some strategies for choosing winning numbers in lottery. One seemingly plausible strategy is to select the hot numbers which most frequently appeared in the past. In this article we investigate the existence of hot numbers in the Korean national lottery called Lotto. A numerical method is proposed to estimate the exact sampling distribution of test statistic for checking the existence of hot numbers among 45 possible numbers of choice.

• 응용통계연구
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• 제7권1호
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• pp.141-147
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• 1994

범죄의 성향이나 도박, 마약 복용 실태 등과 같은 사회적으로나 개인적으로 매우 민감한 문제에 대한 조사에서 세대별 또는 계층별로 상당히 차이가 나는 경우에 단순임의 추출법에 의한 Warner의 확률화 응답 기법보다 효율적인 층화 임의 추출법에 의한 층화 확률화 응답 기법을 제시하고 그 효율성을 증명하였다.

• Journal of the Korean Statistical Society
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• 제35권4호
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• pp.441-452
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• 2006

Here an efficient regression type estimator for a stratified population mean is proposed under the two-phase sampling scheme. While constructing the proposed estimator, it is assumed that the first auxiliary variable x is directly and highly correlated with the study variable y, and the second auxiliary variable z is directly and highly correlated with the first auxiliary variable x. However the variable z is not directly correlated with the variable y, but they are just correlated with each other only due to their direct and high correlation with the variable x. The proposed regression type estimator is found to be always more efficient than the existing estimators defined under the same situation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.49-51
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• 1996

The z-transform method is a basic mathematical tool in analyzing and designing sampled-data control systems. However, since the z-transform method relates only the sampling-instants signals, another mathematical tool is necessary to describe the continous signals between the sampling instants. For this purpose the delayed and the modi fled z-transform methods were developed. The definition of the modi fled z-transform includes a sample in the interval [-T,0] of the original signal in its series expression, where the signal value is always zero for any physical system. From this reason one step skew of the time index always appears in its application formulas. This introduces an unnecessary operation and a gap in linking the mathematical formula and its physical interpretation. Considering the conceptual difficulty and application inconvenience, a method of using the advanced z-transform in analysis of sampled-data control systems is developed as a replacement of the modi fled z-transform. With one formulation of the advanced z-transform, now it is possible to relate both the signals of the sampling instants and those in between without any complication and conceptual difficulty.