• 제목/요약/키워드: statistical analysis method

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강우빈도해석에서 Bootstrap을 이용한 확률분포의 매개변수 추정에 대한 불확실성 해석 (Uncertainty Analysis for Parameter Estimation of Probability Distribution in Rainfall Frequency Analysis Using Bootstrap)

  • 서영민;박기범
    • 한국환경과학회지
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    • 제20권3호
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    • pp.321-327
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    • 2011
  • Bootstrap methods is the computer-based resampling method that estimates the standard errors and confidence intervals of summary statistics using the plug-in principle for assessing the accuracy or uncertainty of statistical estimates, and the BCa method among the Bootstrap methods is known much superior to other Bootstrap methods in respect of the standards of statistical validation. Therefore this study suggests the method of the representation and treatment of uncertainty in flood risk assessment and water resources planning from the construction and application of rainfall frequency analysis model considersing the uncertainty based on the nonparametric BCa method among the Bootstrap methods for the assessement of the estimation of probability rainfall and the effect of uncertainty considering the uncertainty of the parameter estimation of probability in the rainfall frequency analysis that is the most fundamental in flood risk assessement and water resources planning.

LOF를 이용한 ICA 기반 통계적 공정관리의 성능 개선 방법론 (The Use of Local Outlier Factor(LOF) for Improving Performance of Independent Component Analysis(ICA) based Statistical Process Control(SPC))

  • 이재신;강복영;강석호
    • 한국경영과학회지
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    • 제36권1호
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    • pp.39-55
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    • 2011
  • Process monitoring has been emphasized for the monitoring of complex system such as chemical processing industries to achieve the efficiency enhancement, quality management, safety improvement. Recently, ICA (Independent Component Analysis) based MSPC (Multivariate Statistical Process Control) was widely used in process monitoring approaches. Moreover, DICA (Dynamic ICA) has been introduced to consider the system dynamics. However, the existing approaches show the limitation that their performances are strongly dependent on the statistical distributions of control variables. To improve the limitation, we propose a novel approach for process monitoring by integrating DICA and LOF (Local Outlier Factor). In this paper, we aim to improve the fault detection rate with the proposed method. LOF detects local outliers by using density of surrounding space so that its performance is regardless of data distribution. Therefore, the proposed method not only can consider the system dynamics but can also assure robust performance regardless of the statistical distributions of control variables. Comparison experiments were conducted on the widely used benchmark dataset, Tennessee Eastman process (TE process), and showed the improved performance than existing approaches.

2003년부터 2005년까지 안이비인후피부과 학회지에 게재된 논문들의 통계적 분석 방법에 대한 고찰 (The consideration for methods of statistical analysis about the thesis published in the journal of korean oriental medical Ophthalmology & Otolaryngology & Dermatology from 2003 to 2005)

  • 김규석;남혜정;박외숙;김희정;차재훈;김윤범
    • 한방안이비인후피부과학회지
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    • 제19권3호통권31호
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    • pp.134-145
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    • 2006
  • Objective : This study was carried out to investigate what type of assumption and conditions are needed for the application of various statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test and to evaluate that they are used correctly in the research process. Methods : One more methods of statistical analysis were used in 91 papers among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatology from April 2003 to December 2005. So we analysed the type of statistical analysis method in 91 papers(clinical and experimental study) and assessed the their validity of statistical techniques by the check list consisting of 34 items(3 items for validity assessment of descriptive statistics, 6 items for t-test, 7 items for analysis of variance, correlation analysis and regression analysis, respectively, 4 items for chi-square test) Results : 1. The type of 65(40%) cases is experimental trial, the type of 55(34%) cases is case report, the type of 26(16%) cases is clinical trial and the type of 16(10%) cases is review, in 91 papers using statistical techniques among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatol-ogy from April 2003 to December 2005. 2. One more methods of statistical analysis were used in the experimental and clinical study. When we classified 125 units using statistical analysis methods in 91 papers according to statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test, the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of one way ANOVA is 15(12%), the number of non-parametric test 10(8%). 3. After carrying out one way ANOVA, the number of using multiple comparison methods is 15(Scheffe:6(26%), Duncan:4(17%), Dunnett:3(13%), Tukey:2(9%)) out of 23 (total case carrying out one way ANOVA). 8(35%) out of 23 did not enforce multiple comparison methods after carrying out one way ANOVA. 4. From the assessment of validity about 63 cases using statistical techniques(except descriptive statistics), 5(8%) cases are proper, the other 58(92%) are improper, so we recognized a serious misuse of statistical application in our journal. 5. The number of case below 10 sample size in experimental and clinical study(except descriptive statistics) is 31(34%) and frequent. Also the number of case containing no mention of sample size is 41(45%, including culture study). 6. For example of statistical error, there are wrong choice of statistical technique, lack of check on standard assumption(such as standard distribution, equivariance, independence), and so on. Conclusions : We investigated the validity of statistical analysis methods in our journal by check list consisting of 34 items and suggested correct statistical analysis methods. We should practice the spread of education about statistical analysis methods and precis application, enhance objectivity and reliability of our thesis and further correspond with purpose of scientific study.

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고전 임상의학의 통계적 요인 추출방안에 관한 연구 (A Study of the Method of Statistical Factors Analysis from Old Oriental Medical Records in Korea)

  • 박길하;박찬석;박래수;이정화;안상우
    • 한국한의학연구원논문집
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    • 제13권3호
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    • pp.45-51
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    • 2007
  • This Study is to propose the method about statistical factor from the old oriental medical record in Korea. This Study reviews the statistical analysis recently published in the old oriental medical books which are in the Research Report by the Korea Institute of Oriental Medicine at 2007. The results reveal a disease factors, prescription factors.medicines factors, population factors and historical factors by the statistics. The results show that the old oriental medical record for a information system need the interpreting with a information analysts, a statistics analysts and an oriental medical doctors.

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Detecting Multiple Outliers Using the Gaps of Order Statistics

  • Kim, Hyun Chul
    • Communications for Statistical Applications and Methods
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    • 제2권2호
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    • pp.184-197
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    • 1995
  • An objective and one-step detection procedure of multiple outliers is suggested by using the gaps of the order statistics. The detection procedure can be used as a routine outlier detection method of a statistical analysis computer program. The procedure is applied to some examples including the data selected by Kitagawa.

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A Comparative Study of the GPAC Method and the 3-pattern Method for Identifying ARMA Processes

  • Chul Eung KIM;ByoungSeon CHOI
    • Communications for Statistical Applications and Methods
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    • 제3권3호
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    • pp.47-58
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    • 1996
  • The generalized partial autocorrelation (GPAC) method of Woodward and Gray (1981) and the 3-pattern method of Choi (1991) have been used for identifying ARMA processes. The methods are based on the extended Yule-Walker equations. The purpose of this paper is to show the 3-pattern method is superior to the GPAC method through theoretical analysis and computer simulations.

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대한침구학회지 논문의 통계적 오류에 관한 연구 (An Assessment of Statistical Validity of Articles Published in the Journal of Korean Acupuncture & Moxibusition Society - from 1984 to 2002 -)

  • 이승덕
    • Journal of Acupuncture Research
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    • 제21권1호
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    • pp.176-188
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    • 2004
  • This study was carried out to investigate statistical validity of medical articles that used various statistical techniques such as t-test, analysis of variance, correlation analysis, regression analysis and chi-square test. For study 429 original articles using those statistical methods were selected from Journal of Korean Acupuncture & Moxibusition Society published from 1984 to 2002. 429 original articles were reviewed to analyzed the statistical procedures. Results are summarized as follows : 1. In this study 93 articles(21.68%) of 429 ones didn't report statement of statistical method in detail. 2. 53 articles(12.53%) didn't report p-value in correctly, and 245 articles(57.11 %) used mean${\pm}$standard error (Mean${\pm}$SEM.) and 109 articles used mean${\pm}$standard deviation(Mean${\pm}$SD.). All of 23 articles using nonparametric statistical techniques made an error to central tendency or dispersion. 3. 175 articles(59.93%) and 14 articles(4.79%) of 292 ones made an error to description of equal variances and normal distribution. 4. 99 articles(50%) of 185 ones misused t-test and 4 articles of 5 ones misused chi-square test. 5. 28 articles(73.68%) of 38 ones using discrete variable misused parametric technique such as t-test or ANOVA. 2 articles and 1 article of 125 ones choosing paired samples misused independent t-test and Mann-Whitney U test. 6. 20 articles using analysis of variance didn't use multiple comparison.

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침구학회지 논문에 응용된 통계방식에 관한 연구 -1984 창간호부터 2002년 19권 6호까지 19년간- (Analysis of various statistical techniques used in the articles published during last 19 years in The Journal of Korean Acupuncture & Moxibusition Society)

  • 이승덕
    • Journal of Acupuncture Research
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    • 제20권1호
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    • pp.144-158
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    • 2003
  • This study was carried out to investigate what kinds of statistical techniques have been used to analyze data from oriental medicine research, For study, 551 original articles which used statistical techniques in their data analysis were selected form the articles published in The journal of Korean Acupuncture & Moxibustion Society(JKAMS) between 1984 to 2002. among them, 122 articles used descriptive statistics while 429 articles used inferential statistics for data analysis. For that 429 articles, t-test (189 articles), analysis fo variance (111 articles), chi-square test (14 articles), correlation (10 articles), regression analysis (4 articles), factor analysis(5 articles), or nonparametric test (23 articles) were chose to analyze the data. Nonparametric approach has substantial power in case data do not meet the assumption of normality. This method is not only easy to use ut also provides measures of the statistical variation of nominal and ordinal scale. This study shows that more and more recent papers use nonparametric test compared to the old articles. nine different statistical software or packages (SAS, SPSS, Statview, Minitab, Sigma plot, ISP, Graphpad prism, Excel, Access) have been used in the articles published JKMAS. High level statistical techniques such as SAS, SPSS, and Statview are user friendly and used most for acupuncture and Moxibustion research. Including tables and plots in an article facilitates understanding family process data from a descriptive standpoint, minimized erroneous statistical conclusions, and clarifies theoretically important relationships among variables. Table and plots have been used 500 and 233 articles, respectively. A computer procedure is proposed and illustrated with statistical packages using SAS, SPSS, Statview and ISP.

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통계적 데이터 분석방법을 위한 컴퓨터의 활용 I : 붓스트랩 이론과 응용+ (A Computer Intensive Method for Modern Statistical Data Analysis I ; Bootststrap Method and Its Applications)

  • 전명식
    • 응용통계연구
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    • 제3권1호
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    • pp.121-141
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    • 1990
  • 컴퓨터의 발전에 따른 통계방법 중에서 붓스트랩(bootstrap)에 대하여 연구하였다. 특히 추축통계량의 표본분포를 붓스트랩분포로 추정하는데 있어서 계산문제와 이론적인 정당성을 고려하였으며, 모분포의 성격을 나타내는 모수의 붓스트랩 신뢰영역을 몇 가지 사례들에 대해 살펴보았고 사례별로 붓스트랩 방법의 의미를 고찰하였다.

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