• 환경영향평가
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• 제30권3호
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• pp.155-163
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• 2021

환경영향평가의 훼손수목량은 온실가스 배출량, 임목폐기물 산정 등 다양한 부분에 활용되는 환경지표이다. 지금까지 훼손수목량은 식생조사표의 임목밀도에 의존하였고, 이에 따른 표본편향으로 훼손수목량 추정의 불확실성이 가중되었다. 훼손수목량 추정의 정확성을 높이려면 전수조사를 대안으로 제시할 수 있으나 불가능한 것이 현실이다. 대안으로 드론영상을 이용한 개별 수목 탐지 방법이 있으며, 이 연구는 개별 수목 탐지 방법론으로 표본조사(방형구법)와 드론영상 분석법으로 추정된 훼손수목량을 전수조사 결과와 비교하였다. 연구 결과 전수조사 기준으로 드론 영상 분석법은 25주 과대추정 하였고 방형구법(평균)은 58주 과대 추정하였다. 그러나 기존 환경영향평가에서 시행하는 방형구법은 방형구의 개수, 방형구의 위치에 따른 표본편향의 영향을 많이 받을 것으로 예상된다.

• 응용통계연구
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• 제14권2호
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• pp.289-304
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• 2001

2001년에 실시할 $\ulcorner$국민건강.영양조사$\lrcorner$를 위한 새로운 표본설계를 하였다. 본 표본설계에서는 표본의 대표성을 높이기 위해서 기존의 표본가구수는 유지하면서 표본조사구를 증가시키고 새로운 지역 층화변수를 추가로 도입하였다. 또한 추정량의 추정오차 공식을 유도하여 추정의 신뢰성을 측정할 수 있도록 설계하였다.

• Journal of the Korean Statistical Society
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• 제8권2호
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• pp.165-168
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• 1979

For crops that are planted in a lattice layout, sampling designs can be made to take advantage of this regular arrangement. In order to select which tobacco plants to be examined in a survey to estimate disease loss in tobacco a method of, so called, bent plots was devised based on the regularity of plantings in the tobacco fields. We will first describe this sample selection and measurement method and then provide estimators and their bias and variance properties.

• Communications for Statistical Applications and Methods
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• 제6권3호
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• pp.755-760
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• 1999

In multivariate stratified sampling surveys it is general to use a few stratification variables which are highly correlated with the important variables at design stage. But there might be some secondary study variables which are not so highly correlated with those stratification variables. In that case it is not efficient to use the same type of estimator due to the secondary variables as the one base on the important variables. A post-stratified estimation is proposed to increase the efficiency of the estimator with existence of secondary variables. The proposed method is illustrated with a set of fishery household population survey data.

• 응용통계연구
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• 제4권2호
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• pp.137-148
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• 1991

전국 도시 주택가격 동향조사의 목적은 전국 주요 도시의 주택가격 변동상황을 측정하여 주택시장의 동향을 파악함으로써 주택금융 및 정책수립에 기초자료를 제공하는데 있다. 본 조사는 1981년 12월에 최초로 실시한 이후 조사체계를 확대 개선하여 1985년 9월 경제기획원으로부터 일반 통계승인을 받아 실시함으로써 각종 주택정책 및 주택금융의 기초자료로 활용되어 왔다(한국주택은행, 1988).

• Communications for Statistical Applications and Methods
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• 제8권3호
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• pp.719-729
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• 2001

Overlap Maximization is a sampling technique to reduce survey costs and costs associated with the survey. It was first studied by Keyfitz(1951). Ernst(1998) presented a remarkable procedure for maximizing the overlap when the sampling units can be selected for two identical stratified designs simultaneously, But the approach involves mimicking the behaviour of nonlinear function by linear function and so it is less direct, even though the stratification problem for the overlap corresponds directly to the linear programming problem. furthermore, it uses the controlled selection algorithm that repeatedly needs zero-restricted controlled roundings, which are solutions of capacitated transportation problems. In this paper we suggest a comparatively simple procedure to use linear programming in order to maximize the overlap. We show how this procedure can be implemented practically.

• Journal of Communications and Networks
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• 제15권5호
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• pp.443-456
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• 2013

Compressive sensing (CS) is a novel sampling paradigm that samples signals in a much more efficient way than the established Nyquist sampling theorem. CS has recently gained a lot of attention due to its exploitation of signal sparsity. Sparsity, an inherent characteristic of many natural signals, enables the signal to be stored in few samples and subsequently be recovered accurately, courtesy of CS. This article gives a brief background on the origins of this idea, reviews the basic mathematical foundation of the theory and then goes on to highlight different areas of its application with a major emphasis on communications and network domain. Finally, the survey concludes by identifying new areas of research where CS could be beneficial.

• Communications for Statistical Applications and Methods
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• 제10권1호
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• pp.247-256
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• 2003

In this study, we systemize the theoretical validity for applying RRM to three-stage cluster sampling method and derive the estimate and it's variance of sensitive parameter. We derive the minimum variance form under the optimal values of the subsample sizes when the costs are fixed. Under the some given precision, we obtain the optimal values of the subsample sizes and derive the minimum cost form by using them. We apply the three-stage cluster RRM to field survey and suggest some necessary points for practical use.

• 응용통계연구
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• 제18권3호
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• pp.673-687
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• 2005

표본조사에서 이용하는 모수 추론 방법인 설계기반추론과 모형기반추론을 고찰하였다. 설계기반추론은 확률화 원리에 기초를 두고 있는 반면 모형기반추론은 가정한 모형에서 조건부 원리와 우도 원리에 바탕을 두고 있다. 두 추론은 서로 다른 이론적 근거를 사용하기 때문에 이론적 기초에 관한 논쟁이 오래 전부터 있어 왔으며 지금도 진행되고 있다. 이 논문에서는 두 추론 사이에 진행되었던 논쟁의 초점을 살펴보았고 몇 가지 관점에서 두 추론의 장단점을 비교하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.483-488
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• 2014

Aim: This study employed public use National Health and Nutrition Examination Survey (NHANES III) data to investigate the association between urinary cadmium (UDPSI) and all cause, all cancer and prostate cancer mortalities in men. Patients and Methods: NHANES III household adult, laboratory and mortality data were merged. The sampling weight used was WTPFEX6, with SDPPSU6 applied for the probability sampling unit and SDPSTRA6 to designate the strata for the survey analysis. Results: For prostate cancer death, the significant univariates were UDPSI, age, weight, and drinking. Under multivariate logistic regression, the significant covariates were age and weight. For all cause mortality in men, the significant covariates were UDPSI, age, and poverty income ratio. For all cancer mortality in men, the significant covariates were UDPSI, age, black and Mexican race. Conclusions: UDPSI was a predictor of all cause and all cancer mortalities in men as well as prostate cancer mortality.