• Communications for Statistical Applications and Methods
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• 제6권3호
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• pp.761-770
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• 1999

A combination procedure of successive occasions sampling and randomized response method is investigated. Randomized response technique is very simple for use in a telephone survey of a sensitive subject. In the suggested randomized response method. the interviewee replies "yes" or "no" to a randomly selected question and the investigator can estimate the proportion of "yes" or "no" answer. When this procedure is used on successive occasions, not only the proportion supporting a candidate and the time change in this supporting proportion can be derived but also the voters' swing in the trend of voters' support can be estimated. A numerical example is given to show how the suggested sampling strategy can be applied to a practical telephone survey.

• Communications for Statistical Applications and Methods
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• 제6권3호
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• pp.849-860
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• 1999

This paper addresses the issue of estimating regression function with errors in variables using wavelets. We adopt a nonparametric approach in assuming that the regression function has no specific parametric form, To account for errors in covariates deconvolution is involved in the construction of a new class of linear wavelet estimators. using the wavelet characterization of Besov spaces the question of regression estimation with Besov constraint can be reduced to a problem in a space of sequences. Rates of convergence are studied over Besov function classes $B_{spq}$ using $L_2$ error measure. It is shown that the rates of convergence depend on the smoothness s of the regression function and the decay rate of characteristic function of the contaminating error.

• Communications for Statistical Applications and Methods
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• 제26권1호
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• pp.69-78
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• 2019

A structured model with both single-index and varying coefficients is a powerful tool in modeling high dimensional data. It has been widely used because the single-index can overcome the curse of dimensionality and varying coefficients can allow nonlinear interaction effects in the model. For high dimensional index vectors, variable selection becomes an important question in the model building process. In this paper, we propose an efficient estimation and a variable selection method based on a smoothing spline approach in a partially linear single-index-coefficient regression model. We also propose an efficient algorithm for simultaneously estimating the coefficient functions in a data-adaptive lower-dimensional approximation space and selecting significant variables in the index with the adaptive LASSO penalty. The empirical performance of the proposed method is illustrated with simulated and real data examples.

• Communications for Statistical Applications and Methods
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• 제28권3호
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• pp.307-314
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• 2021

We showed that any missing mechanism is reproduced by EMAR or MNAR with equal fit for observed likelihood if there are non-negative solutions of maximum likelihood equations. This is a generalization of Molenberghs et al. (2008) and Jeon et al. (2019). Nonetheless, as MCAR becomes a nested model of MNAR, a natural question is whether or not MNAR and MCAR are testable by using the well-known three statistics, LR (Likelihood ratio), Wald, and Score test statistics. Through simulation studies, we compared these three statistics. We investigated to what extent the boundary solution affect tesing MCAR against MNAR, which is the only testable pair of missing mechanisms based on observed likelihood. We showed that all three statistics are useful as long as the boundary proximity is far from 1.

• 산업경영시스템학회지
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• 제15권26호
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• pp.111-117
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• 1992

In the stock marketing. investor needs speedy and accurate decision making for the investment. A stock exchange index provides the important index of the early of 1993 in Korea using Fuzzy Delphi Method(F. D. M) which is widely used to a mid and long range forecasting in decision making problem. In the Fuzzy Delphi method, considerably qualified experts an first requested to give their opinion seperately and without intercommunication. The forecasting data of experts consist of Triangular Fuzzy Number (T.F.N) which represents the pessimistic, moderate, and optimistic forecast of a stock exchange index. A statistical analysis and dissemblance index are then made of these subject data. These new information are then transmitted to the experts once again, and the process of reestimation is continued until the process converges to a reasonable stable forecast of stock exchange index. The goal of this research is to forecast the stock exchange index using F.D.M. in which subjective data of experts are transformed into quasi -objective data index by some statistical analysis and fuzzy operations. (a) A long range forecasting problem must be considered as an uncertain but not random problem. The direct use of fuzzy numbers and fuzzy methods seems to be more compatible and well suited. (b) The experts use their individual competency and subjectivity and this is the very reason why we propose the use of fuzzy concepts. (c) If you ask an expert the following question: Consider the forecasting of the price index of stocks in the near future. This experts wi11 certainly be more comfortable giving an answer to this question using three types of values: the maximum value, the proper value, and the minimum value rather than an answer in terms of the probability.

• 산경연구논집
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• 제13권7호
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• pp.17-25
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• 2022

Purpose: Environmental contamination has lately been seen as a consequence of the rise in environmental challenges brought on by rapid industrial expansion. At this point, the current research asks an important question about what the factors are to motivate employees' green performance, increasing corporate sustainability. Research design, data and methodology:The current author selected total 19 items to obtain real data and achieve the purpose of this research. For measuring of the causality between the worker's innovative capability and green performance, the current author used the multiple regression statistical tool using U.S. 215 responses in four industry. Results: The statistical finding definitely indicated that there exists the causal linkage between two key factors (Innovation capability and green performance) as well as the strong direction between two constructs. As a result, the current author could accept all hypotheses, checking no existing the multicollinearity of the present constructs with 'TOL' and 'VIF' values. Conclusions: The present research concluded that literature and business management scholars and practitioners will benefit from this study's statistical results. Furthermore, rewarding staff creativity, encouraging quick answers to market movements, and incorporating technology into everyday operations are all ways that companies may cultivate an environmental stewardship culture.

• Communications for Statistical Applications and Methods
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• 제30권1호
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• pp.65-73
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• 2023

Contemporary biomedical data often involve an ill-posed problem owing to small sample size and large number of multi-collinear variables. Partial least squares (PLS) method could be a plausible alternative to an ill-conditioned ordinary least squares. However, in the case of a PLS model that includes a random-effect, how to deal with a random-effect or mixed effects remains a widely open question worth further investigation. In the present study, we propose a modified multivariate PLS method implementing mixed-effect model (PLSM). The advantage of PLSM is its versatility in handling serial longitudinal data or its ability for taking a randomeffect into account. We conduct simulations to investigate statistical properties of PLSM, and showcase its real clinical application to predict treatment outcome of esthetic surgical procedures of human faces. The proposed PLSM seemed to be particularly beneficial 1) when random-effect is conspicuous; 2) the number of predictors is relatively large compared to the sample size; 3) the multicollinearity is weak or moderate; and/or 4) the random error is considerable.

• 한국응급구조학회지
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• 제6권1호
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• pp.141-152
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• 2002

The purpose of this study is to provide the basic materials for searching the way of improvement to heighten the emergency medical welfare level by one step further. To achieve this purpose, the subjects of this study were selected 452 college students in Gwangju, using a random sampling method. The statistical analysis methods utilized for analyzing the collected data are frequency analysis, $x^2$ test. The conclusions obtained from these analyses are as following ; 1. In question about necessary optimum number of persons for rescue first aid activity, health and non-health major college students responded by 39.2%, 45.3% respectively that rescue team 15 people, first aid team 3 people is most suitable. But there was no significant difference in major department(p<0.05). 2. In question about security of the public health doctor and the emergency medical technician, all health and non-health major college students are recognizing necessity urgently, but there was no significant difference in major department(p<0.05). 3. In question about 119 rescue first aid team member applying for an examination qualification grant to the department of EMT's graduate, all health and non-health major college students were highest by 52.9%, 52.4% respectively in "necessity" item. But there was no significant difference in major department(p<0.05). 4. Because rescue first aid equipment level appears higher than 41.7% in non-health major college student's case by 54.2% in health major college student's case, health major college students are recognizing that equipment level should be supplemented more but there was no significant difference in major department(p<0.05). 5. In question about equipment supplement, all health and non-health major college students appeared highest by 64.8%, 69.3% in accident type different special equipment. But there was no significant difference in major department(p<0.05). 6. In question about rescue ambulance car size, we could know being thinking that health and non-health major college student each 61.2%, 56.5% is small and narrow that large size of the rescue ambulance amount need. But there was no significant difference in major department(p<0.05). 7. In question about patient's state is worsened, because rescue first aid equipment is inferior, health major college student responded sometimes 55.1%, many 29.5%. very many by 11.5%, while non-health major college student responded 65.8%, 23.1%, 4.0% respectively. There was significant difference in major department(p<0.05). 8. In question about emergency patient must utilize for 119 rescue ambulance car, all health and non-health major college students appeared highest by 38.8%, 41.3% in "not so" item. In question about rescue first aid team's first-aid treatment ability improves more, all health and non-health major college students appeared highest by 58.1% and 58.7% respectively in "improve" item. In question about "119 rescue ambulance car must go more rapidly than now", all health and non-health major college students are recognizing that should be quicker by 58.1%, 60.9% respectively. When called to 119 all health and non-health major college students responded highest by 55.5%, 53.3% respectively that we must receive first-aid treatment direction from a doctor. In question about "119 rescue ambulance car must be made the pay system", all health and non-health major college students responded 74%, 80% respectively in "not so" item. There was significant difference in major department(p<0.05). In conclusions, In oder to provide superior rescue first aid service to people, a public health doctor should be placed in the situation room inside the fire station so that the doctor could instruct the proper emergency treatment suitable for each situation to the rescue first aid team. Also, national education about a first-aid treatment that do to all people is necessarily necessary in emergency delivery system and this should be spread extensively through school education and broadcasting medium and education should be gone side by side, and see that will can save emergency patients' life which is more when these education consists continuously fixed period for public institution of policeman, fire officer etc. specially. And for reinforcement of patient transfer system, public organization must procure special ambulance car so that emergency patient receive first aid treatment while transfer.

• 한국전자거래학회지
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• 제22권1호
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• pp.15-35
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• 2017

공공사업 타당성 평가나 대안 선정에서는 대부분 AHP 기법을 활용하여 대안별 가중합 방식으로 최종 점수를 산정하고 그 값이 가장 큰 대안을 선택하고 있다. 특히 타당성 분석과 같은 경우에는 최종 점수가 0.5보다 큰 대안을 선택하게 되는데, 그 값이 0.5보다 얼마나 커야 의사결정이 의미있고 설득력있는 판단이라고 할 수 있는지에 대한 합리적인 기준 없이 적용되고 있다. 한국개발연구원(KDI)에서 제시한 방법론에는 사업진행 대안의 종합 점수가 0.5 근처에 있는 경우를 회색 영역으로 구분하여 신중한 결정을 하도록 제시하고 있는데, 세부기준에 관한 이론적 검토는 빈약하다. 반면, 통계적 검정의 개념을 도입하여 시도된 분석사례에서는 가중합 평가 점수의 확률분포로서 정규분포 또는 베타분포를 가정하였으나, 이에 대한 분포적 타당성은 제시되지 않았다. 본 논문에서는 현재 다양한 분야에서 적용되고 있는 가중합 평가 방식의 사례를 검토하여 그 결과의 통계적 검정의 필요성을 제기하고, 통계적 검정을 위하여 특정 분포를 가정하지 않는 비모수적 검정 방법을 제시한다. 그리고 본 연구에서 제시한 방법을 국방 분야의 사례에 적용하고 그 함의와 함께 향후 연구의 발전방향을 제안한다.

• 대한물리치료과학회지
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• 제5권4호
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• pp.777-784
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• 1998

The purpose of this study was to determine the diagnosis and treatment patterns for frozen shoulder patients. It was used Delphi survey techniques and the subjects were 35 expect physical therapists who agreed participated in the study. The data were analyzed by the x2-test at 0.05 level of statistical significance. The results were as follows : 1. In accordance with open ended question, 11 diagnosis and 14 treatment are collected in the first investigation. 2. In accordance with close ended question, they were selected 5 diagnosis and 5 treatments criteria from the results of the first replied questionnaire. 3. Finally, the third close ended questionnaire, they were selected 3 main driteria of the diagnosis and treatments from the results of the second investigation. The physical therapists prefer to 1) History 2) ROM test 3) Palpation & Inspection in the diagnostic field, and 1) EST and Convex-Concave rule 2) Codman's exercise and MFR 3) Deep friction massage in the treatment field.