• 제목/요약/키워드: Statistics topic

검색결과 133건 처리시간 0.025초

주성분회귀와 고유값회귀에 대한 감도분석의 성질에 대한 연구 (A study on the properties of sensitivity analysis in principal component regression and latent root regression)

  • 신재경;장덕준
    • Journal of the Korean Data and Information Science Society
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    • 제20권2호
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    • pp.321-328
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    • 2009
  • 회귀분석에서 설명변수들 사이에 상관이 높으면 최소제곱추정법에서 구한 회귀계수들의 정도가 떨어진다. 다중공선성이라 불리는 이 현상은 실제 자료분석에서 심각한 문제를 야기시킨다. 이 다중공선성의 문제를 극복하기 위한 여러 가지 방법이 제안되었다. 능형회귀, 축소추정량 그리고 주성분분석에 기초한 주성분회귀와 고유값회귀등이 있다. 지난 수십 년간 많은 통계학자들은 일반적인 중 회귀에서 감도분석에 관해 연구하였으며, 주성분회귀, 고유값회귀와 로지스틱 주성분회귀에 대해서도 같은 주제로 연구하였다. 이 모든 방법에서 주성분분석은 중요한 역할을 하였다. 또한, 많은 통계학자들이 주성분분석과 관련된 다변량 방법에서 감도분석에 대해 연구를 하였다. 본 연구논문에서는 주성분회귀와 고유값회귀를 소개하고, 또한 주성분회귀와 고유값회귀에서 감도분석의 방법을 소개하고, 마지막으로 이들두방법에 대한 감도분석의 성질에 대해 논의하였다.

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한국특허정보의 통계분석에 관한 연구 (A Study on the Statistical Analysis of Korea Patent Information)

  • 엄대호;장영배;정의섭
    • 정보관리연구
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    • 제41권3호
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    • pp.27-44
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    • 2010
  • 지금까지 특허분석에 관한 연구는 특허지도(Patent Map; PM)분석을 수행하여 기술동향을 분석하고 있으나, 주제에 대한 검색결과를 엑셀 등을 이용하여 그래프화하여 출원빈도에 대한 추이를 나타내는 것이 대부분이다. 이러한 분석은 특정주제에 대한 것으로 국가의 산업이나 국제적인 산업의 동향을 직접 비교 분석하기에는 미흡한 실정이다. 본 연구에서는 PM분석의 신뢰성을 높이기 위해 통계분석의 필요성을 제시하고, 1990년부터 2004년에 출원된(출원번호 기준) 한국특허 전체를 대상으로 연도별, 분류별(IPC Section 분류)로 각 국가(한국, 미국, 일본, 독일)의 출원빈도를 통계적으로 유의한 수준을 분석하였다. 또한 국가 및 기술 분류에 대한 출원빈도에 대해 포아송 회귀분석을 수행하고, 통계 적으로 유의한 수준에 따른 평가를 R&D에 활용할 수 있도록 하였다.

정규-지수분포에 대한 최소밀도함수승간격 추정법 (Minimum Density Power Divergence Estimation for Normal-Exponential Distribution)

  • 박노진
    • 응용통계연구
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    • 제27권3호
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    • pp.397-406
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    • 2014
  • 최소밀도함수승간격 추정법은 Baus 등 (1998)에 의해 처음 소개된 이후 많은 관심의 대상이 되었다. 최소밀도함수승간격 추정량은 우수한 로버스트 성질을 갖고 효율성도 최우추정량에 필적한 것으로 알려져 있다. 본 논문에서는 생물정보학에서 사용되는 노말-지수 분포에 근거한 추정량을 최소밀도함수승간격 추정법을 사용하여 구하는 방법을 다루고자 한다. 그런데 그 과정에서 간격을 적분을 통해 구하는 것이 매우 어려움으로 인해 직접적인 적분 대신 라플라스 근사를 시도할 것을 제안한다. 그 결과 추정량이 다소 효율성이 줄어들지만 로버스트 성질을 갖고 있음을 수학적 방법과 모의실험을 통하여 보였다.

앙상블 SVM 모형을 이용한 기업 부도 예측 (Bankruptcy prediction using ensemble SVM model)

  • 최하나;임동훈
    • Journal of the Korean Data and Information Science Society
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    • 제24권6호
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    • pp.1113-1125
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    • 2013
  • 기업의 부도를 예측하는 것은 회계나 재무 분야에서 중요한 연구주제이다. 지금까지 기업 부도예측을 위해 여러 가지 데이터마이닝 기법들이 적용되었으나 주로 단일 모형을 사용함으로서 복잡한 분류 문제에의 적용에 한계를 갖고 있었다. 본 논문에서는 최근에 각광받고 있는 SVM (support vector machine) 모형들을 결합한 앙상블 SVM 모형 (ensemble SVM model)을 부도예측에 사용하고자 한다. 제안된 앙상블 모형은 v-조각 교차 타당성 (v-fold cross-validation)에 의해 얻어진 여러 가지 모형 중에서 성능이 좋은 상위 k개의 단일 모형으로 구성하고 과반수 투표 방식 (majority voting)을 사용하여 미지의 클래스를 분류한다. 본 논문에서 제안된 앙상블 SVM 모형의 성능을 평가하기 위해 실제 기업의 재무비율 자료와 모의실험자료를 가지고 실험하였고, 실험결과 제안된 앙상블 모형이 여러 가지 평가척도 하에서 단일 SVM 모형들보다 좋은 성능을 보임을 알 수 있었다.

Plain 조직 니트 의류의 소매산 형태 연구 (A Study of Sleeve Cap in the Knitwears with Plain Stitch)

  • 홍수숙;서미아
    • 복식문화연구
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    • 제14권3호
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    • pp.404-417
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    • 2006
  • The purpose of this thesis, therefore, is to examine the shaping methods and the knitting drafts of sleeve cap in the knitwears which are currently used by the manufacturers; to study the curve forms of sleeves in knitwears by analyzing synthetically the results of investigating the problems of knit wear sleeves; to present the most suitable sleeve cap for the knitwears. As the studying methods, I collected the basic data from the working-level persons of knit wear manufacturers, examined the knitting draft in the knitwears, and from that, made three kinds of comparative experimental garments and one kind of research experimental one as 10G and 16G. In doing so, I showed the sleeve cap suitable for the knitwears with plain stitch after operating sensual evaluation with Liker's 5-point rating measure. The analysis of data was handled with statistics by using SPSS Ver. 12.0; the method of statistics was executed by Frequency Analysis, Trust Analysis, one-way ANOVA, and Duncan test according to each topic of the research. As the result of the sensual evaluation of the experimental garments produced from the study, the research experimental garment looks better than the comparative experimental one in both 10G and l6G; has less extra folds around the front part of sleeve cap; looks more natural in sleeve caps of the body part and of a sleeve. From this, I am able to figure out that the research experimental garment looks better than the comparative experimental one produced by knit wear manufacturers. In addition, I can come to know that the different knitting of the front line and the back one of armhole in the knitwears has a favorable impact on improving the appearance of a sleeve.

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아토바스타틴의 새로운 약물 적응증 탐색을 위한 비정형 데이터 분석 (Analysis of Unstructured Data on Detecting of New Drug Indication of Atorvastatin)

  • 정휘수;강길원;최웅;박종혁;신광수;서영성
    • Journal of health informatics and statistics
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    • 제43권4호
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    • pp.329-335
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    • 2018
  • Objectives: In recent years, there has been an increased need for a way to extract desired information from multiple medical literatures at once. This study was conducted to confirm the usefulness of unstructured data analysis using previously published medical literatures to search for new indications. Methods: The new indications were searched through text mining, network analysis, and topic modeling analysis using 5,057 articles of atorvastatin, a treatment for hyperlipidemia, from 1990 to 2017. Results: The extracted keywords was 273. In the frequency of text mining and network analysis, the existing indications of atorvastatin were extracted in top level. The novel indications by Term Frequency-Inverse Document Frequency (TF-IDF) were atrial fibrillation, heart failure, breast cancer, rheumatoid arthritis, combined hyperlipidemia, arrhythmias, multiple sclerosis, non-alcoholic fatty liver disease, contrast-induced acute kidney injury and prostate cancer. Conclusions: Unstructured data analysis for discovering new indications from massive medical literature is expected to be used in drug repositioning industries.

간호사가 인지하는 간호관리자의 윤리적 리더십 측정 도구 K-ELW의 타당화 연구 (A Validation Study of the Modified Korean Version of Ethical Leadership at Work Questionnaire (K-ELW))

  • 김정언;박은준
    • 대한간호학회지
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    • 제45권2호
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    • pp.240-250
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    • 2015
  • Purpose: The purpose of this study was to validate the Korean version of the Ethical Leadership at Work questionnaire (K-ELW) that measures RNs' perceived ethical leadership of their nurse managers. Methods: The strong validation process suggested by Benson (1998), including translation and cultural adaptation stage, structural stage, and external stage, was used. Participants were 241 RNs who reported their perceived ethical leadership using both the pre-version of K-ELW and a previously known Ethical Leadership Scale, and interactional justice of their managers, as well as their own demographics, organizational commitment and organizational citizenship behavior. Data analyses included descriptive statistics, Pearson correlation coefficients, reliability coefficients, exploratory factor analysis, and confirmatory factor analysis. SPSS 19.0 and Amos 18.0 versions were used. Results: A modified K-ELW was developed from construct validity evidence and included 31 items in 7 domains: People orientation, task responsibility fairness, relationship fairness, power sharing, concern for sustainability, ethical guidance, and integrity. Convergent validity, discriminant validity, and concurrent validity were supported according to the correlation coefficients of the 7 domains with other measures. Conclusion: The results of this study provide preliminary evidence that the modified K-ELW can be adopted in Korean nursing organizations, and reliable and valid ethical leadership scores can be expected.

Prospects and Challenges of Implementing Cloud Accounting in Bangladesh

  • SAHA, Trina;DAS, Sumon Kumar;RAHMAN, Md. Moshiur;SIDDIQUE, Fahimul Kader;UDDIN, Mohammad Gias
    • The Journal of Asian Finance, Economics and Business
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    • 제7권12호
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    • pp.275-282
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    • 2020
  • The objectives of this study are to understand the meaning of cloud accounting, to investigate whether it is favorable for performance of the organization and what are the challenges if a country like Bangladesh wants to implement it. Primary data have been collected from 300 respondents selected from the field of accounting, such as accountants, accounting graduates of different universities, teachers and bankers. To measure the reliability and validity of the sample size and data, KMO and Bartlett's test have been adopted and the results proved to be reliable and valid for the study. Regression analysis has been done to find out the positive impact of cloud accounting on organizational performance and negative impact of cloud accounting on existing accounting system of the organization. The results of regression analysis supported our alternative hypotheses that cloud accounting can improve organizational performance, but it has also some negative impacts. Descriptive statistics have been used to find out the probable challenges that may be faced by organizations that want to implement it. This is a pioneering study because there is little research on this topic, thus it is expected to develop awareness about cloud accounting in field of accounting in Bangladesh.

정보활용이 고령층 삶에 미치는 영향에 관한 연구 (The Effects of Information Application of the Elderly on Their Lives)

  • 이미숙;김희섭;홍순구
    • 한국IT서비스학회지
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    • 제14권2호
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    • pp.33-49
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    • 2015
  • The purpose of this study is to analyse the effect of information application of the elderly on their lives through analysing the key papers on the topic. To achieve the aim of this study, we searched the papers from RISS, KISS, DBpia and the National Assembly Library of the Republic of Korea, using keywords such as 'the elderly and informationization,' 'the elderly and information application,' and 'mediator effect.' In the search process, we did not limited the publication year or journal types. A total of 476 papers were searched as the result of the initial search. Based on three researchers consent of selection criteria, we finally selected 19 papers and analysed the important mediator variables between the information application and the life satisfaction or happiness. Using the content analysis, we analysed the quantitative analyses (including sample characteristics and sociodemographic statistics) and qualitative analyses (including result interpretation and policy implication about the elderly information education). After in-depth analysis of the papers, we built a table organized by the independent variable and the mediator variable. With the results, several implications were discussed and contributions are also explained.

자폐성장애 아동 부모의 삶의 전환과정 측정도구 개발 (Development of a Scale to Measure Life Transition Process in Parents of Children with Autism)

  • 이애란;홍선우;주세진
    • 대한간호학회지
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    • 제42권6호
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    • pp.861-869
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    • 2012
  • Purpose: The purpose of this research was to develop a scale to measure the life transition process of parents of children with autism, against the backdrop of a lack of research on this topic. Methods: Seventy preliminary items were drawn from previous qualitative research, and content validity was tested by three professors as well as three parents of children with autism. A questionnaire survey was also done between August 2011 and February 2012. Data were collected from 207 parents of children with autism and analyzed using descriptive statistics, item analysis, Cronbach's alpha, Pearson correlation coefficients, and factor analysis with the SPSS Win 15.0 program. Results: Twenty-nine items were selected to constitute the appropriate measuring scale and categorized into 5 factors explaining 63.2% of the total variance. The 5 factors were named; stages of denial (5 items), wandering (6 items), devotion (7 items), frustration (3 items), and finally acceptance (8 items). Cronbach's alpha for the 29 items was .80. Conclusion: The results of this study not only suggest assessment criteria for the life transition process of parents who have children with autism but also provide basic directions for program development to provide differentiated support and care at each stage.