• Journal of the Korean Statistical Society
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• 제23권1호
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• pp.207-216
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• 1994

Count data are often overdispersed, and an appropriate test for the existence of the overdispersion is necessary. In this paper we derive a score test based on the extended quasi-likelihood and the pseudolikelihood after adjusting to the Bartlett factor. Also, we compare it with Levene (1960)'s F-type test suggested by Ganio and Schafer (1992).

• 유통과학연구
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• 제13권9호
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• pp.103-112
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• 2015

Purpose - This paper aims to provide a step-by-step approach to factor analytic procedures, such as principal component analysis (PCA) and exploratory factor analysis (EFA), and to offer a guideline for factor analysis. Authors have argued that the results of PCA and EFA are substantially similar. Additionally, they assert that PCA is a more appropriate technique for factor analysis because PCA produces easily interpreted results that are likely to be the basis of better decisions. For these reasons, many researchers have used PCA as a technique instead of EFA. However, these techniques are clearly different. PCA should be used for data reduction. On the other hand, EFA has been tailored to identify any underlying factor structure, a set of measured variables that cause the manifest variables to covary. Thus, it is needed for a guideline and for procedures to use in factor analysis. To date, however, these two techniques have been indiscriminately misused. Research design, data, and methodology - This research conducted a literature review. For this, we summarized the meaningful and consistent arguments and drew up guidelines and suggested procedures for rigorous EFA. Results - PCA can be used instead of common factor analysis when all measured variables have high communality. However, common factor analysis is recommended for EFA. First, researchers should evaluate the sample size and check for sampling adequacy before conducting factor analysis. If these conditions are not satisfied, then the next steps cannot be followed. Sample size must be at least 100 with communality above 0.5 and a minimum subject to item ratio of at least 5:1, with a minimum of five items in EFA. Next, Bartlett's sphericity test and the Kaiser-Mayer-Olkin (KMO) measure should be assessed for sampling adequacy. The chi-square value for Bartlett's test should be significant. In addition, a KMO of more than 0.8 is recommended. The next step is to conduct a factor analysis. The analysis is composed of three stages. The first stage determines a rotation technique. Generally, ML or PAF will suggest to researchers the best results. Selection of one of the two techniques heavily hinges on data normality. ML requires normally distributed data; on the other hand, PAF does not. The second step is associated with determining the number of factors to retain in the EFA. The best way to determine the number of factors to retain is to apply three methods including eigenvalues greater than 1.0, the scree plot test, and the variance extracted. The last step is to select one of two rotation methods: orthogonal or oblique. If the research suggests some variables that are correlated to each other, then the oblique method should be selected for factor rotation because the method assumes all factors are correlated in the research. If not, the orthogonal method is possible for factor rotation. Conclusions - Recommendations are offered for the best factor analytic practice for empirical research.

• 응용통계연구
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• 제6권2호
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• pp.319-328
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• 1993

뉴톤-랩슨 반복법이 최우추정량에 접근하는 비율이 초기값에 따라 가속화함을 보았다. 그러 므로 최우추정량을 구하기 어려운 경우에 통계적 목적 - Bahadur 효율, 콰지(Quasi) 우도비 검정 통계량의 점근분포, Bartlett 정정계수(correction factor)등 - 에 따라 뉴톤-랩슨 반복 의 횟수를 정하여 쓸 수 있다.

• 대한간호학회지
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• 제43권5호
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• pp.587-594
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• 2013

Purpose: The purpose of this study is to provide researchers with a simplified approach to undertaking exploratory factor analysis for the assessment of construct validity. Methods: All articles published in 2010, 2011, and 2012 in Journal of Korean Academy of Nursing were reviewed and other relevant books and articles were chosen for the review. Results: In this paper, the following were discussed: preliminary analysis process of exploratory factor analysis to examine the sample size, distribution of measured variables, correlation coefficient, and results of KMO measure and Bartlett's test of sphericity. In addition, other areas to be considered in using factor analysis are discussed, including determination of the number of factors, the choice of rotation method or extraction method of the factor structure, and the interpretation of the factor loadings and explained variance. Conclusion: Content validity is the degree to which elements of an assessment instrument are relevant to and representative of the targeted construct for a particular assessment purpose. This measurement is difficult and challenging and takes a lot of time. Factor analysis is considered one of the strongest approaches to establishing construct validity and is the most commonly used method for establishing construct validity measured by an instrument.

• 산경연구논집
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• 제10권5호
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• pp.7-20
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• 2019

Purpose - This study provides appropriate procedures for EFA to help researchers conduct empirical studies by using PLS-SEM. Research design, data, and methodology - This study addresses the absolute and relative sample size criteria, sampling adequacy, factor extraction models, factor rotation methods, the criterion for the number of factors to retain, interpretation of results, and reporting information. Results - The factor analysis procedure for PLS-SEM consists of the following five stages. First, it is important to look at whether both the Bartlett test of sphericity and the KMO MSA meet the qualitative criteria. Second, PAF is a better choice of methodology. Third, an oblique technique is a suitable method for PLS-SEM. Fourth, a combined approach is strongly recommended to factor retention. PA should be used at the onset. Next, it is recommended using the K1 criterion. In addition, it is necessary to extract factors that increase the total variance explanatory power through the PVA-FS. Finally, it is appropriate to select an item with a factor loading into 0.5 or higher and a communality of 0.5. Conclusions - It is expected that the accurate factor analysis processed for PLS-SEM as previously presented will help us extract more precise factors of the structural model.

• 한국식품조리과학회지
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• 제21권2호
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• pp.155-162
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• 2005

The purpose of this study was to identify factors associated with sanitation and cleanliness regarding the importance of family restaurant employees in the Ulsan and Busan areas. Accordingly, this study conducted a suey questionnaire consisting of 28 measures of food-service as well as major subject descriptors. From the results, the frequency, descriptive, factor, correspondence analysis, major findings and marketing implications could be summarized as follows: First, 6 factors were extracted: cooking and control factor, food and tableware handling factor, personal cleanliness condition factor, purchase and receiving factor, unit food material store factor and Kitchen utensil sanitation factor. KMO and Bartlett' stest statistics showed that the data fitted the factor analysis well. Results of factor analysis, average variance extracted estimates and shared variance showed that the convergent and discriminant validity of 6 factors are supported and Cronbach's alpha showed that the internal consistency of the 6 factors was supported. Second, correspondence analysis indicated that statistically significant relationships existed between some of the family restaurant employee sanitation and cleanliness factors and the family restaurant enterprise.

• 한국생활과학회지
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• 제15권2호
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• pp.251-259
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• 2006

The purpose of this study is to identify main effect of gender and expenditure, and interaction effect of gender by expenditure on satisfaction with foodservices of western restaurants. Accordingly, this study surveyed questionnaires concerning 20 measures of foodservice as well as major subject descriptors. The result of this study was as follows: KMO and Bartlett's test statistics showed that the data well fitted a factor analysis. Results of the factor analysis, average variance extracted estimates, and shared variance showed that the convergent and discriminant validities of 5 factors were supported, and Cronbach's alpha also showed that the internal consistencies of 5 factors were supported. But there was an interaction effect between independent variables and covariate on service quality factor. This study, therefore, used food decor factor, facility factor, food quality factor, and food value factor as dependent variables in two way 3$\times$2 design factorial ANCOVA. It was found that there were no main effects of gender and expenditure on those four factors. It was however revealed that there was an interaction effect of gender by expenditure on food decor factor.

• 한국수자원학회논문집
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• 제45권11호
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• pp.1131-1141
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• 2012

본 연구에서는 댐 용수공급능력에 영향을 미치는 요인들을 요인분석 통계기법을 사용하여 추출하였으며, 그 결과를 이용하여 댐 용수공급능력 추정을 위한 다중회귀모형을 개발하였다. 21개 다목적댐과 12개 생공용수전용댐을 대상으로 하였으며, 다목적댐과 생공용수전용댐으로 구분하여 요인분석을 수행하였다. 댐 용수공급능력에 영향을 미치는 변수로 유역면적, 유입량, 유효저수량, 생공용수량 등급, 농업용수량 등급, 하천유지유량 등급, 하천관리 등급, 평균강우량 등급을 선정하였다. 변수들의 상관계수 행렬점검, Bartlett의 구형성 점검, KMO 표본적합도 점검을 실시하여 변수들의 요인분석에 대한 적합성을 확인하였다. 변수들은 다목적댐의 경우 3개 요인, 생공용수전용댐의 경우 2개 요인으로 분류되었으며, 요인들을 Varimax법을 사용하여 회전시켰다. 요인분석 결과는 댐 용수공급능력에 영향을 미치는 변수들이 합리적으로 선정되었고, 이들이 요인으로 적절하게 분류되었음을 보여주었다. 요인점수를 설명변수로 사용하여 연간용수공급량을 추정할 수 있는 다중회귀모형을 개발하였으며, 개발된 모형의 정확성을 평가하고 적용방법을 제시하였다. 결론적으로 댐 용수공급능력에 영향을 미치는 것으로 파악된 변수 및 요인은 댐 계획 및 설계에 유용하게 활용될 수 있을 것으로 사료된다.

• 대한보건연구
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• 제44권4호
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• pp.99-109
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• 2018

연구목적: "건강정보이해능력은 개인이 보건의료 관련 의사결정을 스스로 하는데 충분한 건강정보와 보건의료서비스를 제대로 얻고 처리하고 이해하는 능력"으로 정의된다. 고령자는 건강정보이해능력이 특히 취약한 인구집단이다. 이 연구는 Chew 등이 개발한 척도를 적용하여 우리나라 고령자의 건강정보이해능력을 측정하기 위한 도구의 신뢰도와 타당도를 검증하였다. 연구방법: 자료는 단면조사로 수집된 2016년 '서울 고령자 건강과 기능조사' 60~79세 725명 응답자를 대상으로 분석하였다. 대상자를 무작위로 두 표본으로 나누어 표본 A (n=400)는 탐색적 요인분석과 척도의 타당화를 위한 분석에 사용하고, 표본 B (n=325)는 확증적 요인분석을 위해 사용하였다. 설문지는 번역-역번역, 전문가 교차검토 등을 통해 최종 12문항으로 구성하였고, 내적신뢰도 분석을 통해 최종 8문항을 선택하였다. 연구결과: 연구결과 8개 설문문항은 2개의 요인 구조를 보였고, 탐색적 요인분석 결과 신뢰도와 타당도가 높았다 (KMO=.872, Bartlett's ${\chi}^2=2431.248$, df=28, p<.001). 확증적 요인분석은 추출된 이 두 요인 구조(건강정보 "이해"와 건강정보 "활용")의 구성타당도가 충족되는 결과를 보였다(${\chi}^2=53.386/df=19$, GFI=.960, CFI=.979, TLI=.969, RMSEA=0.075). 결론: 본 연구는 이 도구가 고령자의 건강정보이해능력을 측정하는 도구로 타당도가 있음을 증명한다.

• 한국식품조리과학회지
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• 제20권4호
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• pp.371-379
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• 2004

The purpose of this study was to identify factors associated with high satisfaction with foodservices in family restaurant. Accordingly, this study surveyed questionnaire concerning 20 measures of foodservice as well as major subject descriptors. The result of this study were as follows. KMO and Bartlett's test statistics showed that the data fitted factor analysis well. Results of factor analysis, average variance extracted estimates and shared variance showed that the convergent and discriminant validitys of 3 factors are supported, and cronbach's alpha showed that the internal consistency of 3 factors is supported. It was found that expensive groups, except gender groups and frequency of purchase groups, were differentially associated with high levels of overall satisfaction with foodservices. Multivariate analyses showed that satisfaction with service factor was the best predictor of overall satisfaction, followed by facilities factor. Three factors emerged from the logistic regression analysis as predictors of level of overall satisfaction. Overall, approximately 77% of university students could be correctly classified as being satisfied or unsatisfied. Finally, the results of the study provide some insights into the market-oriented types of foodservice marketing strategies or tactics to enable family restaurant to effectively manage and more competitive.