• 대한간호학회지
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• 제44권4호
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• pp.446-457
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• 2014

Purpose: This study was done to evaluate the effects of psychosocial interventions on cortisol and immune response in adult patients with cancer. Methods: MEDLINE via PubMed, Cochrane Library CENTRAL, EMBASE, CINAHL and domestic electronic databases were searched. Twenty controlled trials (11 randomized and 9 non-randomized trials) met the inclusion criteria with a total of 862 participants. Methodological quality was assessed using the Cochrane's Risk of Bias for randomized studies and the Risk of Bias Assessment tool for non randomized studies. Data were analyzed using the RevMan 5.2.11 program of Cochrane library. Results: Overall, study quality was moderate to high. The weighted average effect size across studies was -0.32 (95% CI [-0.56, -0.07], p=.010, $I^2 $=45%) for cortisol concentration, -0.62 (95%CI [-0.96,-0.29], p<.001, $I^2 $=0%) for T lymphocyte (CD3) and -0.45 (95%CI [-0.74, -0.16], p=.003, $I^2 $=0%) for Th lymphocyte (CD4) numbers. Psychosocial interventions were not effective for Tc lymphocyte (CD4), NK cell, monocyte, and cytokine response. Conclusion: Although these results provide only small evidence of successful immune modulation, they support the conclusion that psychosocial interventions can assist cancer patients in reducing emotional distress and improving immune response.

• 한국산학기술학회논문지
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• 제14권2호
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• pp.625-633
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• 2013

본 다중반응표면 최적화는 다수의 반응변수(품질특성치)를 동시에 고려하여, 입력변수의 최적 조건을 찾는 것을 목적으로 한다. 지금까지 다중반응표면 최적화를 위하여 다양한 방법이 제안되어 왔는데, 그 중 평균제곱오차 최소화법은 다수의 반응변수의 평균과 표준편차를 동시에 고려하여 최적화하는 방법이다. 이 방법은 기본적으로 평균과 표준편차가 동일한 가중치를 가지고 있다는 것을 전제로 하고 있다. 그러나 문제의 상황에 따라 평균과 표준편차에 서로 다른 가중치를 부여해야 하는 경우도 있다. 이에 본 논문에서는 기존의 평균제곱오차를 확대하여 평균과 표준편차에 서로 다른 가중치도 부여할 수 있도록 가중평균제곱오차 최소화법을 제안하고자 한다.

• 수산경영론집
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• 제40권3호
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• pp.147-167
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• 2009

The objective of this study is to analyze the determinants of at-home laver consumption expenditures using the data from a survey of households implemented in 2009. It happened that non-response ratios of monthly expenditures on dry laver and flavored laver among sampled households are 18.8% and 25.6%. Accordingly, this study tries to analyze the determinants affecting at-home laver consumption expenditures by using type II tobit model, one of sample selection models, to deal with sample selection bias caused from non-response data. Analysis results show the age variable positively affects expenditures on dry laver but negatively contributes to expenditures on flavored laver. In addition, the household size, the household's income, the degree of preference for laver have positive relationships with both expenditures. Household size elasticity and income elasticity of the expenditure on dry laver are estimated as 0.220 and 0.251. In the case of flavored laver, these elasticities are estimated as 0.484 and 0.261. Such analysis results can provide information on division of the at-home laver consumption market into groups with high willingness to expense and implementation of detailed marketing strategies to increase at-home laver consumption. The methodology of this study can be applied to consumer preference analysis on other marine products and other analyses on sample with non-response data in the fishery research.

• Journal of the Korean Statistical Society
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• 제9권2호
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• pp.145-172
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• 1980

Draper and Lawrence (1965a) have given mixture designs for three factors when all the mixture components can vary on the entire factor space so that the region of interest is an equilateral triangle in two dimensions. In this paper their work is extended to the cases when the region of interest is an echelon, parallelogram, pentagon or hexagon, because of the restirctions imposed on some or all of the mixture components. The principles used in the choice of appropriate designs are those originally introduced by Box and Draper(1959). It is assumed that a response surface equation of first order is fitted, but there is a possibility of bias error due to presence of second order terms in the true model. Minimum bias designs for several cases of restricted regions of interest are illustrated.

• 응용통계연구
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• 제30권1호
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• pp.69-82
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• 2017

R-지수(representativeness indicator)는 무응답이 발생했을 때 표본의 대표성을 나타내주는 지표이다. 표본의 대표성은 모수 추정의 정확성(accuracy)과 관계가 있으며 정확성은 편향(bias)와 관계가 있다. 따라서 표본의 대표성을 나타내는 R-지수가 높으면 대표성이 높아 편향이 없고 정확성이 높은 결과를 얻을 수 있다. R-지수는 일반화선형모형의 로짓 또는 프로빗 모형을 적합한 후 얻어진 경향 점수(propensity score)에 의해 계산된다. 본 논문에서는 R-지수와 이질적인 층별 응답률과의 관련성을 연구하였으며 편향, 제곱근 RMSE 등과 같은 비교통계량이 무응답에 얼마나 민감한지 등을 모의실험을 통하여 살펴보았다. 또한 변형된 2010년 경제총조사 자료를 이용하여 실제 자료분석도 실시하였다.

• 품질경영학회지
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• 제23권3호
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• pp.102-112
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• 1995

Estimation of each of mean response, difference between mean responses and derivatives of the response function is a possible objective of a response surface design. These objectives are to be achieved simultaneously when an experiment is designed to improve mean response. For the situations where departure from the assumed model is suspected, first and second order designs for improving mean response are obtained by combining minimum bias designs for the individual design objectives. D- and A-optimalities are used for selecting specific second order designs. The results are applied to central composite designs.

• Korean Journal of Radiology
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• 제20권4호
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• pp.649-661
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• 2019

Objective: To systematically review the evaluation of the diagnostic accuracy of pre-treatment apparent diffusion coefficient (ADC) and change in ADC during the intra- or post-treatment period, for the prediction of locoregional failure in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods: Ovid-MEDLINE and Embase databases were searched up to September 8, 2018, for studies on the use of diffusion-weighted magnetic resonance imaging for the prediction of locoregional treatment response in patients with HNSCC treated with chemoradiation or radiation therapy. Risk of bias was assessed by using the Quality Assessment Tool for Diagnostic Accuracy Studies-2. Results: Twelve studies were included in the systematic review, and diagnostic accuracy assessment was performed using seven studies. High pre-treatment ADC showed inconsistent results with the tendency for locoregional failure, whereas all studies evaluating changes in ADC showed consistent results of a lower rise in ADC in patients with locoregional failure compared to those with locoregional control. The sensitivities and specificities of pre-treatment ADC and change in ADC for predicting locoregional failure were relatively high (range: 50-100% and 79-96%, 75-100% and 69-95%, respectively). Meta-analytic pooling was not performed due to the apparent heterogeneity in these values. Conclusion: High pre-treatment ADC and low rise in early intra-treatment or post-treatment ADC with chemoradiation, could be indicators of locoregional failure in patients with HNSCC. However, as the studies are few, heterogeneous, and at high risk for bias, the sensitivity and specificity of these parameters for predicting the treatment response are yet to be determined.

• 품질경영학회지
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• 제16권1호
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• pp.49-58
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• 1988

When a question in a sample survey is sensitive or highly personal, respondents may prefer not to give truthful answers. To eliminate the resulting evasive answer bias Warner suggested a randomized response model. In this paper, a modification of Warner's method is presented and compared with Warner's method. The relation between this modified method and an unrelated question method is also discussed.

• Journal of the Korean Data and Information Science Society
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• 제27권2호
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• pp.315-325
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• 2016

조사결과의 신속성이 요구되는 선거여론조사의 특성상 짧은 시간에 유권자들의 의견을 파악할 수 있고 저렴한 조사비용이라는 장점 때문에 낮은 응답률이라는 심각한 결함에도 불구하고 대부분 선거여론조사는 전화조사로 이루어진다. 현재 국내에서 실시되는 많은 선거여론조사는 연령별, 성별, 지역별 인구수 또는 유권자수에 비례하여 할당된 수만큼 조사하는 방식을 취하고 있다. 무응답이 발생하여 초기에 할당된 수만큼 조사가 이루어지지 않은 경우, 응답자들의 가중치를 조정하여 추정하는 방법을 사용한다. 본 연구에서는 무응답이 존재하는 경우, 현재 국내 여론조사에서 사용하는 추정량의 편의와 분산의 편의를 수리적으로 도출하였다. 이 편의는 응답집단과 무응답집단 간의 의사 차이와 무응답률의 크기에 비례한다. 또, 2012년 대선 선거여론 조사 자료를 기초로 전화 선거여론조사에서의 응답률을 산출하였는데, 평균 약 14.4%에 불과하였다. 한편, 자체적으로 실시한 '전화 선거여론조사에 대한 의식조사'에서, 응답자들이 전화 선거여론조사에 응답하지 않는 가장 큰 이유로 "귀찮아서"를 가장 많이 선택하였고, 여론조사 응답률이 가장 낮은 20대가 가장 많이 선택한 이유도 "귀찮아서"였다. 따라서 응답률을 높이기 위해서는 인센티브를 지급하는 등 조사대상자들의 응답 동기를 높이기 위한 보다 적극적인 노력이 필요하다.

• Communications for Statistical Applications and Methods
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• 제2권2호
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• pp.243-248
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• 1995

The problem of optimal design for a nonparametric regression with binary data is considered. The aim of the statistical analysis is the estimation of a quantal response surface in two dimensions. Bias, variance and IMSE of kernel estimates are derived. The optimal design density with respect to asymptotic IMSE is constructed.