• 제목/요약/키워드: non-parametric statistics

검색결과 131건 처리시간 0.026초

데이터 구조에 강건한 K 관리도의 관리 모수 결정 (Robust determination of control parameters in K chart with respect to data structures)

  • 박잉근;이성임
    • Journal of the Korean Data and Information Science Society
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    • 제26권6호
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    • pp.1353-1366
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    • 2015
  • 공정의 안정성을 평가하기 위해 사용되는 Shewhart 관리도 기법은 최근 다양한 분야에서 널리 응용되고 있지만, 품질 특성치에 대한 엄격한 확률분포를 가정한다. 하지만 현업에서 수집되고 있는 데이터의 확률분포는 알려진 경우가 많지 않으며, 다변량 데이터로 확장될수록 확률분포를 결정하는데 더 큰 어려움이 따른다. 이러한 문제점을 해결하기 위해 다양한 비모수 관리도 기법이 연구되었는데, 최근 연구되고 있는 비모수 관리도 기법 중 하나인 RBF (Radial Basis Function) 커널 기반의 SVDD (Support Vector Data Description) 관리도는 관리상태 하의 데이터 영역에 대한 경계를 결정함으로써 공정의 이상상태를 탐지하는 기법으로 K 관리도로 불리우며, 다양한 분야에서 적용되고 있다. 그런데 K 관리도를 적용하기 위해서는 관리도의 성능을 결정짓는 커널모수 등의 선택이 중요하며, 관리도를 작성하기 전에 미리 결정되어야 한다. 이를 위해 기존의 연구들은 격자 탐색법 등을 활용하여 모수를 결정하고 있지만, 선택 가능한 범위에 대한 반복적인 계산으로 최적값을 선택하고 있어 계산 비용이 커지고 또 시간 등의 문제로 실제 문제에 적용하기 어려운 점이 있다. 따라서 본 연구에서는 데이터의 구조에 따라 모의실험을 통해 선택 가능한 영역에서의 효율성을 비교 검토하고, 이를 바탕으로 쉽게 적용할 수 있는 새로운 모수 선택 방법을 제안하고자 한다. 이를 통해 데이터 구조에 대해 강건함을 보이는 모수의 선택과 K 관리도의 구성을 논의하고 실제 자료에 적용해 보았다.

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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2007 한국 소아청소년 성장곡선 및 정상혈압 분포 개발 방법론 (The methodology for developing the 2007 Korean growth charts and blood pressure nomogram in Korean children and adolescents)

  • 이순영;김윤남;강연지;장명진;김진흠;문진수;이종국;오경원;김영택;남정모
    • Clinical and Experimental Pediatrics
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    • 제51권1호
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    • pp.26-32
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    • 2008
  • 목 적 : 1998년과 2005년 신체발육표준 제정사업 자료를 이용하여 2007년 소아청소년 성장곡선의 개발과정에서에 이용된 성장곡선 및 혈압분포 개발 방법론을 제시하고자 하였다. 방 법 : 성장곡선은 1998년과 2005년 자료를 이용해서 각 백분위수의 성장곡선 모형을 추정하고 LMS를 방법을 이용하여 최종 성장곡선을 생산하였다. 연령과 신장별 혈압 성장곡선은 2005년 자료를 이용하여 남녀별로 고정효과 회귀모형을 적용하여 산출하였다. 결 과 : 2007 소아청소년 성장곡선 및 혈압분포 표를 제시할 수 있었다. 결 론 : 2007년 성장곡선과 혈압분포 표는 현재 가용한 자료와 최신의 통계적 방법을 최대한 활용한 국내 최초의 결과로서 향후 지속적인 발전을 위한 논의와 연구가 필요하다.

평균이동분할과 연결요소를 이용한 도로추출 알고리즘 (A Road Extraction Algorithm using Mean-Shift Segmentation and Connected-Component)

  • 이태희;황보현;윤종호;박병수;최명렬
    • 디지털융복합연구
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    • 제12권1호
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    • pp.359-364
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    • 2014
  • 본 논문은 평균이동방법과 연결요소방법을 이용하여 도로 영역을 추출하는 알고리즘을 제안하였다. 평균 이동 방법은 중심 모드를 찾기 위한 비모수적 통계 방법으로 컬러 영상을 분할하는데 효율적이다. 일반적으로, 영상의 중 하단에 위치하는 정보를 활용하여 도로의 특징점이 추출된다. 이 특징점과 분할된 컬러 영상을 이용하면, 도로의 영역을 추출할 수 있다. 그러나, 도로의 위치정보와 색상정보만으로 도로영역을 추출할 경우, 잡음과 도로 이외의 영역까지 추출되는 단점이 있다. 본 논문에서는 모폴로지 열기 닫기 연산을 이용하여 잡음을 제거하고, 연결요소 방법을 통하여 가장 큰 영역의 부분만을 추출하여 도로 영역으로 결정하는 방법을 제안한다. 제안된 방법은 실험을 통하여 잡음 제거와 보다 정확한 도로 검출됨을 검증한다.

아파트공사 기능직 종사자와 단순노무 근로자의 직무스트레스와 작업능력에 관한 연구 (A Study on Job Stress and Work Ability of Technical Workers and Simple Labor Workers in Apartment Construction)

  • 이종빈;장성록
    • 한국안전학회지
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    • 제29권5호
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    • pp.129-135
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    • 2014
  • In recent studies, construction industry workers with higher job stress and lower work ability were more likely to experience accidents at their workplace. Likewise, fatal accidents rate was higher among simple labor workers compared to technical workers. Therefore the evaluation of a worker's job stress and work ability seems to be important in preventing the occurrence of fatal accidents. To search for ways to reduce job stress and to improve work ability, the current study conducted a job stress analysis based on age, years of service, skill level, hobbies, sleep patterns, and monthly income. For this, the Korean occupational stress questionnaire short form and the Work Ability Index (WAI) developed by the Finnish Institute of Occupational Health (FIOH) were used. In this study, SPSS 12.0K statistics program was used for statistical analysis and significance was verified by the Kruskal-Wallis test and non-parametric tests. The results of this study can be summarized as follows : (1) Simple labor workers had higher job stress and less work ability than technical workers. (2) The more experienced workers had lower job stress and higher work ability. (3) In the case of workers who slept a lot, work ability was higher and job stress was less. (4) Monthly income influenced on the job stress and work ability. (5) Job stress and work ability in accordance with the age difference was not significant.

질 관리에 대한 간호사의 사고유형과 문제해결력 (A Study on the Nurses' Thinking Skills and Problem Solving Abilities for Quality Management in Healthcare Services)

  • 고자경;박연옥
    • 한국의료질향상학회지
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    • 제5권2호
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    • pp.238-256
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    • 1998
  • Background : There have been many studies and efforts about quality management in health services, but these were not focused on the thinking ability of the personnel. In this study, We planned to define the relationship between Quality Management(QM) and thinking skill, and analyzed critical thinking skill and problem solving ability of the nurses for QM in healthcare. Methods : We surveyed 260 nurses in 3 hospitals by using questionnaires about thinking skills and QM from November 18 to 28, 1998. The response rate was 76.9%. We described and analyzed the data by descriptive statistics, t-test, ANOVA, Pearson correlation, and non-parametric Friedman test using SPSS Win 7.5. Results : This study revealed that 1) understanding level of QM concepts was very low and insufficient, 2) willingness to practice QM in healthcare was relatively high and affirmative, but the positive attitude taking part in the program of QM is very low(4.5%), 3) even though the necessity of QM was recognized, actual application of critical thinking skills and problem solving abilities is lacking, 4) the production of idea for QM was the most insufficient, and so the next of the problem solving process(QA cycle) was the same. Conclusion : Based on the above results, we can conclude that understanding the concepts of QM is very important to solve problems about QM in healthcare. For development of thinking skill to promote critical problem solving ability for QM in healthcare, it is necessary to improve curriculum of nursing education and teaching-learning methods of QM strategy and technique.

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Preferences of Malaysian Cancer Patients in Communication of Bad News

  • Eng, Tan Chai;Yaakup, Hayati;Shah, Shamsul Azhar;Jaffar, Aida;Omar, Khairani
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권6호
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    • pp.2749-2752
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    • 2012
  • Background: Breaking bad news to cancer patients is a delicate and challenging task for most doctors. Better understanding of patients' preferences in breaking bad news can guide doctors in performing this task. Objectives: This study aimed to describe the preferences of Malaysian cancer patients regarding the communication of bad news. Methodology: This was a cross-sectional study conducted in the Oncology clinic of a tertiary teaching hospital. Two hundred adult cancer patients were recruited via purposive quota sampling. They were required to complete the Malay language version of the Measure of Patients' Preferences (MPP-BM) with minimal researcher assistance. Their responses were analysed using descriptive statistics. Association between demographic characteristics and domain scores were tested using non-parametric statistical tests. Results: Nine items were rated by the patients as essential: "Doctor is honest about the severity of my condition", "Doctor describing my treatment options in detail", "Doctor telling me best treatment options", Doctor letting me know all of the different treatment options", "Doctor being up to date on research on my type of cancer", "Doctor telling me news directly", "Being given detailed info about results of medical tests", "Being told in person", and "Having doctor offer hope about my condition". All these items had median scores of 5/5 (IQR:4-5). The median scores for the three domains were: "Content and Facilitation" 74/85, "Emotional Support" 23/30 and "Structural and Informational Support" 31/40. Ethnicity was found to be significantly associated with scores for "Content and Facilitation" and "Emotional Support". Educational status was significantly associated with scores for "Structural and Informational Support". Conclusion: Malaysian cancer patients appreciate the ability of the doctor to provide adequate information using good communication skills during the process of breaking bad news. Provision of emotional support, structural support and informational support were also highly appreciated.

In vitro study of fracture strength of provisional crown materials

  • Karaokutan, Isil;Sayin, Gulsum;Kara, Ozlem
    • The Journal of Advanced Prosthodontics
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    • 제7권1호
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    • pp.27-31
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    • 2015
  • PURPOSE. The purpose of this report was to evaluate the effect of the fabrication method and material type on the fracture strength of provisional crowns. MATERIALS AND METHODS. A master model with one crown (maxillary left second premolar) was manufactured from Cr-Co alloy. The master model was scanned, and the data set was transferred to a CAD/CAM unit (Yenamak D50, Yenadent Ltd, Istanbul, Turkey) for the Cercon Base group. For the other groups, temporary crowns were produced by direct fabrication methods (Imident, Temdent, Structur Premium, Takilon, Systemp c&b II, and Acrytemp). The specimens were subjected to water storage at $37^{\circ}C$ for 24 hours, and then they were thermocycled (TC, $5000{\times}$, $5-55^{\circ}C$) (n=10). The maximum force at fracture (Fmax) was measured in a universal test machine at 1 mm/min. Data was analyzed by non-parametric statistics (${\alpha}$=.05). RESULTS. Fmax values varied between 711.09-1392.1 N. In the PMMA groups, Takilon showed the lowest values (711.09 N), and Cercon Base showed the highest values (959.59 N). In the composite groups, Structur Premium showed the highest values (1392.1 N), and Acrytemp showed the lowest values (910.05 N). The composite groups showed significantly higher values than the PMMA groups (P=.01). CONCLUSION. Composite-based materials showed significantly higher fracture strengths than PMMA-based materials. The CADCAM technique offers more advantages than the direct technique.

홍채표지와 비만지표와의 상관성 연구 (A Study on the Correlation between Iris Markings and Obesity Indices)

  • 임영우;박성일;박영재;박영배
    • 대한한의진단학회지
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    • 제17권2호
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    • pp.112-121
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    • 2013
  • Objectives This study analyze the correlation between iris markings and the obesity level shown in body composition indices. And It quantitatively evaluates iris markings according to the level of obesity to improve a clinical application plan for the iris analysis. Methods This study analyzed the iris and body composition through the quantization of iris markings for 28 female patients. It calculated descriptive statistics by using SPSS 13.0 and investigated correlation coefficients of non-parametric Spearman in order to analyze the relation between iris markings and body composition indices. Results Considering the correlation between iris markings and body composition indices, an area of the pupil had a significant positive correlation with height and with fat-free amount such as body water, protein, and minerals. BMI showed significant positive correlations with the length of the autonomic nerve wreath and the ratio of the autonomic nerve wreath, and the area of the autonomic nerve wreath. Moreover, the number of lacunas in the pancrea area had a significant positive correlation with weight and BMI. Conclusions This study objectifies the quantification of iris markings to identify the correlation between iris markings and the level of obesity. The study results will be used as a basic data to make standards for the diagnosis of obesity, the treatment of related diseases, and the diagnosis of iris markings for prevention.

예비치매 부양자의 재가서비스 이용에 관한 연구 -치매특별등급(5등급) 중심으로 (A Study on the Intention to Use Community Care Service by Pre-Caregivers Based on Dementia Under the Long-Term Care Insurance System for the Aged -Special dementia rating (5 rates) in the focus)

  • 손이숙;이경수;정재욱
    • 한국임상보건과학회지
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    • 제4권3호
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    • pp.603-614
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    • 2016
  • Purpose. The purpose of this study was to provide basic data regarding the intention to use community care service based on special grading for dementia in the South Korean Society. Methods. A survey was conducted using a questionnaire adapted on the basis of literature review regarding the first to fourth grade under the long-term care insurance system for the aged from May 1 to 30, 2015 and a total of 272 questionnaires were statistically processed using SPSS 21.0. Frequency analysis, descriptive statistics, and cross-tabulation analysis were performed. The non-parametric type of test, ${\chi}^2$ test, was used for statistical testing. Results. This study obtained the following results: First, caregivers had greater intention to ask recipients to use daytime and nighttime care service. Second, there were statistically significant differences in caregivers' education, occupation, monthly average income, co-residence status, intimacy, and care-giving burden (emotional, financial, and social) and recipients' activities of daily living, instrumental activities of daily living, mental health status, dementia status, and intention to use community care service based on special grading for dementia. Conclusions. There are very few statistical data and academic materials regarding special grading for dementia, which has recently been established. The results of this study are therefore expected to help make a systematic analysis of the intention to use community care service by caregivers based on special grading for dementia.