• Communications for Statistical Applications and Methods
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• 제15권6호
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• pp.1013-1026
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• 2008

신용평가모형의 판별력에 대한 적합성 검정방법으로 콜모고로프-스미르노프(K-S) 통계량이 널리 사용되고 있다. K-S 통계량을 통한 모형의 판별력 판단기준으로는 표본수에 의존하는 K-S 검정통계량의 임계값보다 매우 큰 기준인 $0.3{\sim}0.4$의 수준이 일반적으로 적용된다. 본 논문에서는 모의실험을 통해 일반적 판단기준의 타당성을 살펴보았다. 모의실험 결과 국내에서 개발된 대부분의 신용평가모형의 결과를 바탕으로 구한 K-S 통계량은 현재 적용하고 있는 판단기준보다 큰 값을 갖는다는 것을 발견하였다. 따라서 어떠한 신용평가모형 이라도 좋은 판별력을 갖는다고 해석할 수 있다. 본 연구에서는 표본크기와 불량률 그리고 제II종 오류율에 따른 대안적인 임계값을 제안한다.

• 공학교육연구
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• 제21권5호
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• pp.32-39
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• 2018

The purpose of this study was to develop and validate a behaviorally anchored rating scale for peer evaluation in group projects based on social interdependence theory. A mixed method involving a qualitative and quantitative approach was used in this study. In the qualitative study, both the individual and group interviews were conducted to college students regarding their cooperative learning experiences. Data from this qualitative research was analyzed based on 5 elements of cooperative learning and 'critical incidents' were extracted from students' own voices that would serve as specific rating criteria in the scale. Once the 'critical incidents' have been incorporated into the scale, validation from 3 independent experts was conducted. In the quantitative study, correlations with relevant variables were analyzed to examine the criteria-referenced validity. Findings suggest that the behaviorally anchored rating scale for peer evaluation in group projects can be used in various team-based learning contexts.

• Journal of the Korean Data and Information Science Society
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• 제20권2호
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• pp.261-272
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• 2009

신용평가모형에서 두 집단의 판별력 검정방법 중의 하나로 두 분포함수의 동일성 검정을 위한 비모수적인 Kolmogorov-Smirnov (K-S) 검정방법이 대표적으로 적용되고 있다. 본 연구에서는 신용평가모형에서 두 분포함수의 동일성 검정을 위하여 K-S 검정 방법 외에 Cramer-Von Mises, Anderson-Darling, Watson 검정방법들을 소개하고 Joseph (2005)의 기준에 대응하는 판단기준을 제안한다. 또한 신용평가 자료와 유사한 상황 하에서의 모의실험을 통해서 불량률, 표본크기 그리고 제II종 오류율을 고려한 대안적인 판단기준을 제시하고 그 적용방법에 대해서 살펴본다.

• 대한가정학회지
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• 제36권6호
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• pp.95-108
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• 1998

This study is the second study which was aimed to validate the Infant/ Toddler Environment Rating Scale(ITERS). The test-retest reliability included 10 infant/toddler classes among 30 national/public and private child care centers in Inchon city which had been observed in the first validation study. The Spearman's correlation coefficient for test-retest reliability was ranged from .52 to .84. In addition, two raters observed 10 family day care centers in Inchon city, where two observers independently rated each centers on the ITERS during a single visit. The Spearman's correlation coefficient for interrater reliability was ranged from.72 to .99 For the second measure of content validity, experts who were working in day care centers and who were graduate students, lecturers, or professors majoring child studies rated the appropriateness of each ITERS items for the provision of high-quality programs for infants and toddlers, using a 1(low) to 5(high) scale. The mean rating was ranged from 2.52 to 4.52. In sum, when the rating scores were analyzed by the type of child care centers, national/public child care centers have better quality than private or family child care centers.

• Journal of the Korean Data and Information Science Society
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• 제19권3호
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• pp.789-800
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• 2008

Current credit evaluation models based on financial data make use of smoothing estimated default ratios which are transformed from each financial variable. In this work, some problems of the credit evaluation models developed by financial experts are discussed and we propose improved credit evaluation models based on the stepwise variable selection method and Box-Cox transformed data whose distribution is much skewed to the right. After comparing goodness-of-fit tests of these models, the validation of the credit evaluation models using statistical methods such as the stepwise variable selection method and Box-Cox transformation function is explained.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.679-683
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• 2005

The technique which connects Generalized Regression Neural Networks Model(GRNNM) with Genetic Algorithm (CA) is used to derive rating curve in the river basin. GRNNM architecture consists of 4 layers ; input, hidden, summation and output layer. GA method is applied to estimate the optimal smoothing factor when GRNNM is trained. The derivation of rating curve using GRNNM is considered different kinds of hydraulic characteristics such as water stage, area and mean velocity and is applied two stage stations; Sunsan and Jungam. Furthermore, it is compared with conventional curve-fitting method. Through the training and validation performance, the results show that GRNNM is much superior as compared to the conventional curve-fitting method.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2005년도 공동추계학술대회
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• pp.571-578
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• 2005

Corporate credit rating analysis has drawn a lot of research interests in previous studies, and recent studies have shown that machine learning techniques achieved better performance than traditional statistical ones. This paper applies support vector machines (SVMs) to the corporate credit rating problem in an attempt to suggest a new model with better explanatory power and stability. To serve this purpose, the researcher uses a grid-search technique using 5-fold cross-validation to find out the optimal parameter values of kernel function of SVM. In addition, to evaluate the prediction accuracy of SVM, the researcher compares its performance with those of multiple discriminant analysis (MDA), case-based reasoning (CBR), and three-layer fully connected back-propagation neural networks (BPNs). The experiment results show that SVM outperforms the other methods.

• 응용통계연구
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• 제21권6호
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• pp.1065-1075
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• 2008

신용평가모형 개발과 적합성 검정 연구에서 부도율분포로부터 부도기업과 정상기업의 판별력을 검정하는 방법으로 비모수적인 방법인 Kolmogorov-Smirnov(K-S) 검정방법을 많이 사용한다. 모집단에 대한 누적분포함수를 알고있으며 이 분포함수가 두 개의 분포함수로 분할되었다는 가정하에서 두 분포함수 동일성을 검정하는 신용평가 연구에서 스코어 또는 부도율이 다양한 확률분포를 따른다고 가정하고 기존의 K-S 통계량과 수정된 K-S 통계량을 비교 토론한다.

• Journal of Electrical Engineering and Technology
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• 제3권2호
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• pp.243-253
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• 2008

This paper deals with the analysis, design, and implementation of a single phase AC-DC Zeta converter with high frequency transformer isolation and power factor correction(PFC) in two modes of operation, discontinuous current mode of operation(DCM), and continuous current mode of operation(CCM). A Digital Signal Processor(DSP) based implementation is carried out for validation of the Zeta converter developed design in discontinuous mode of operation. A comparison of both modes of operation is presented for a 1kW power rating from the point of view of steady state and dynamic behavior, power quality, simplicity, control technique, device rating, and converter size. The experimental results of a developed prototype of Zeta converter are presented for validation of the developed design. It is observed that CCM is most suitable for higher power applications where it requires some complex control and sensing of the additional variables.

• 대한가정학회지
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• 제35권6호
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• pp.235-248
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• 1997

This study was aimed to validate the Infant/Toddler Environment Rating scale (ITERS). The rating scale was translated and adjusted appropriately by two researchers majoring child studies. An item-by-item comparison of the ITERS with criteria of NAEYC was conducted as the measure of content validity. 88% of the items of the ITERS was covered on the NAEYC criteria. Criterion validity was assessed by comparing ITERS scores and the Assessment Profile for early childhood Programs scores. The total correlation of two scores was .87. The sample for the inetrater reliability and internal consistency studies included 30 infant/toddler classes in 30 day care center in Inchon city. Two observers independently rated each class on the ITERS during a single visit. The Spearman's correlation coefficient for interater reliability on the overall scale was .74. For the measure of internal consistency, the Cronbach's Alpha score on the overall scale was .93. The rating results show that national/public child care centers have better quality in Adult Needs and Learning Activities subscales than private child care centers have.