• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1664-1675
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• 2021

In order to verify the statistical performance of the nonparametric tests used in the MARSSIM approach, all plausible contamination distribution types that can be encountered in a survey area should be investigated. As the first of such investigations, this study aims to perform the verification for normal distribution of the contamination in a survey area by simulating the collection of random samples from it through the Monte Carlo simulation. The results of the simulations conducted for a total of 81 simulation cases showed that Sign test and WRS test both exhibited an excellent statistical performance: 100% for the former and 98.8% for the latter. Therefore, in final status surveys of the MARSSIM approach, a high statistical performance can be expected in applying the nonparametric hypothesis tests to survey areas whose net contamination can be assumed to be normally distributed.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2003년도 춘계 학술발표회 논문집
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• pp.137-142
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• 2003

We discuss why sample design by mathematical programming can be beneficial to practical surveys. We illustrate some developments of software for sample design using mathematical programming in several statistical organizations. Also, we present certain restrictions on the use of mathematical programming.

• 한국직업건강간호학회지
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• 제16권2호
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• pp.177-187
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• 2007

Purpose: We were to identify the differences of "Job stress" and "Depression scores" in the divided groups by self-efficacy. And the factors affecting Depression scores were analyzed. Method: This study was conducted from July 2006 to September 2006. Collected 295 surveys were used in this study among 311 surveys since 16 surveys offered insufficient data. SPSS for Windows 10.0 was used to analyse the data. Result: We identified the factors of "Occupational climate", "Job control", "Job demand" as affecting the depression scores in the lower self-efficacy group by the multi-variables statistical analysis. And this statistical model had 12.5% explainable power. Also, the factors of "Occupational climate" were identified as affecting the depression scores in the higher self-efficacy group. And the statistical model had 9.0% explainable power. Conclusion: In the lower self-efficacy group, the scores of the job stress and depression were significantly higher. Therefore, in the lower self-efficacy group, the self-efficacy promotion programs should be needed for prevention of the related occupational diseases. The factors related job stress were identified as affecting the depression scores in both lower and higher self-efficacy groups. Therefore, job stress management program should be prepared for stress loading workers.

• 천문학회보
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• 제44권2호
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• pp.35.4-35.4
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• 2019

Understanding the interplay between galaxies and dark matter in the universe is one of key challenges in modern astrophysics. This provides an important test of structure formation scenarios and cosmological models. I discuss three aspects of this test: (1) comparing the matter distribution from galaxy redshift surveys with that from weak-lensing surveys, (2) statistical comparison of large-scale structures between observations and cosmological simulations, and (3) multi-wavelength study of galaxies. These tests underscore the importance of combining photometric and spectroscopic surveys in observations along with cosmological simulations for exploring and understanding the structure formation.

• 응용통계연구
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• 제18권2호
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• pp.311-328
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• 2005

본 논문은 농어가경제조사에서 발생하는 무응답을 처리하는 방법에 관한 것이다. 농어가경제조사는 모두 층화다단표집을 한 후 가중평균으로 모평균을 추정하므로 이에 적합한 대체법으로 가중핫덱 대체법을 고려하여 가중핫덱 대체 절차와 모평균 추정법, 그리고 대응되는 분산추정법을 고찰하였다. 그리고 모의실험을 통하여 가중핫덱 대체가 두 조사에 적용될 수 있음을 보였고 수정된 잭나이프 분산추정법을 사용하면 추정치의 신뢰도도 효과적으로 나타낼 수 있음을 보였다. 또한 두 조사에 적용할 수 있는 대체군 형성 절차를 제시하고, 예로써 각각 4가지 방안을 비교, 분석하였다. 그리고 그 중 가장 효율적인 방안을 결과로써 제시하였다.

• 대한간호학회지
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• 제42권1호
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• pp.48-55
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• 2012

Purpose: The aim of this study was to compare statistical methods to control response bias in nursing activity surveys. Methods: Data were collected at a medical unit of a general hospital. The number of nursing activities and consumed activity time were measured using self-report questionnaires. Descriptive statistics were used to identify general characteristics of the units. Average, Z-standardization, gamma regression, finite mixture model, and stochastic frontier model were adopted to estimate true activity time controlling for response bias. Results: The nursing activity time data were highly skewed and had non-normal distributions. Among the 4 different methods, only gamma regression and stochastic frontier model controlled response bias effectively and the estimated total nursing activity time did not exceeded total work time. However, in gamma regression, estimated total nursing activity time was too small to use in real clinical settings. Thus stochastic frontier model was the most appropriate method to control response bias when compared with the other methods. Conclusion: According to these results, we recommend the use of a stochastic frontier model to estimate true nursing activity time when using self-report surveys.

• Communications for Statistical Applications and Methods
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• 제16권1호
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• pp.169-183
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• 2009

The simplicity and wide application of Greenberg et al. (1971) prompts to propose a set of alternative estimators of population total for multi-character surveys that elicit simultaneous information on many. sensitive study variables. The proposed estimators take into account the already known rough value of the correlation coefficient between Y(the characteristic under study) and p(the measure of size). These estimators are biased, but it is expected that the extent of bias will be smaller, since the proposed estimators are suitable for situations in between those optimum for the usual estimators and the estimators based on multi-characters for no correlation. The relative efficiency of the proposed estimators has been studied under a super population model through empirical study. It has been found through simulation study that a choice of an unrelated variable in the Greenberg et al. (1971) model could be made based on its correlation with the auxiliary variable used at estimation stage in multi-character surveys.

• Communications for Statistical Applications and Methods
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• 제16권2호
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• pp.317-323
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• 2009

Recently not even government polices but small town decisions are based on the survey data/information, so the most of government agencies/organizations demand various sample surveys in each fields for more detail information. However in conducting the sample survey, nonresponse problem rises very often and it becomes a major issue on judging the accuracy of survey. For that matters, one solution ran be using the administration data. However unfortunately most of administration data are restricted to the common users. The other solution can be the imputation. Therefore several method, of imputation are studied in various fields. In this study, in stead of the simple regression imputation method which is commonly used, factor score regression method is applied specially to the incomplete data which have the unit and item misting values in survey data. Here for simulation study, Consumer Expenditure Surveys in Korea are used.

• Communications for Statistical Applications and Methods
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• 제16권6호
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• pp.1031-1036
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• 2009

Under recent dramatic declines in response rates, various procedures have been considered among survey practitioners to reduce nonresponse in order to avoid its potential impairment to the inference. In the random digit dialing telephone surveys, substantial efforts are often required to obtain the initial contact for the screener interview. To reduce a burden with higher data collection costs, refusal conversion can be administered only to a random portion of the sample, reducing nonresponse (bias) with an expense of sample variability increment due to the associated weight adjustment. In this paper, we provide ways to determine the optimal subsampling rate using a linear cost model. Our approach for refusal subsampling is to predetermine a random portion from the full sample and to apply refusal conversion efforts if needed only to the subsample.

• 융합정보논문지
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• 제10권8호
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• pp.250-258
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• 2020

본 연구를 통해 에스테틱 샵을 이용하는 고객들의 행동 의도에 긍정적인 영향을 미칠 수 있는 서비스 스케이프와 미적 노동, 감정반응, 고객 행동 의도 간 요소를 분석하고 그에 대한 인과관계를 도출하고자 한다. 최근 3개월 이내 울산 및 경남지역 에스테틱 샵 이용자 약 280명을 대상으로 설문 조사한 설문지 257부를 실증분석하였다. 표본 자료는 Statistical power analysis using 3.1 analysis를 이용하여 다중회귀 분석하였고 SPSS 21.0 및 AMOS 21.0으로 통계처리 하였다. 에스테틱 서비스의 서비스 스케이프, 미적 노동이 고객의 긍정적인 반응에 영향을 미치고, 긍정적 반응에 의한 고객만족도는 재방문에 긍정적인 영향 관계를 형성하여 매개 효과가 있다는 것을 확인하였다. 또한 에스테틱 서비스에 대한 만족과 지속적 이용 의도 선행요인들의 구조 관계를 밝힘으로써 실무적 시사점 도출에 긍정적 기여를 하였다. 향후 연구에서는 에스테틱 서비스 이용자의 특성을 고려한 대상자의 다양한 연령층과 지역 확대 연구가 요구되어진다.