• Title/Summary/Keyword: Statistical methodology

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A Study on the Statistical Methods Used in KCI Listed Journals of Traditional Korean Medicine from 1999 to 2008 (국내 한의학 학술지에 사용된 통계기법에 대한 고찰: 1999-2008 한국연구재단 등재지를 중심으로)

  • Lee, Yong-Jae;Kwak, Min-Jung;Jung, Hae-Ree;Ha, Hyun-Yee;Chae, Han
    • Korean Journal of Oriental Medicine
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    • v.18 no.2
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    • pp.55-64
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    • 2012
  • Objectives: This study was performed to review the use of statistical analysis methods for the Traditional Korean Medicine studies listed on the Korea Citation Index from 1999 to 2008. Methods: A total of 4217 studies published on four journals of Traditional Korean Medicine were screened and 2682 articles using statistical methods were selected for the review. The selected studies were analysed according to their published year, statistical method and statistical package for use. Results: Statistical methods were used steadily in 64.6% of the articles after 2001, the most used statistical methods(57%) were mean difference comparison between 2 groups. The number of statistical methods mostly used in one article was identified as one in 1931 articles (72.0%). Duncan (36.8%) and Tukey (26.5%) were used for the ANOVA post hoc analysis. SPSS was most frequently used 68% out of Statistical package programs.(the number of mean difference comparison among more than 3 groups was continuously increasing and that makes post hoc being used. skills of statistical methods need to be diversified.) Conclusion: The interest on the proper use of statistical analysis in the research is increasing. This study will contribute to the Evidence-based Teaching on research methodology in Traditional Korean Medicine.

A Review of Statistical Analysis Methods Applied on Traditional Korean Medicine Research (한의학 연구에 활용된 통계분석 방법에 대한 고찰)

  • Jang, Seon-Il;Yun, Young-Gab;Choi, Kyoung-Ho
    • Herbal Formula Science
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    • v.17 no.1
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    • pp.75-83
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    • 2009
  • Objective : The purpose of this study is to indicate of problems in statistical analysis method of "The Korean Journal of oriental Medical Prescription" and we will be proposed the useful application of the statistical analysis method. Methods : In this paper, we were analysed statistical analysis methodology from published journal articles "The Korean Journal of Oriental Medical Prescription" December, year 2000 to December, year 2008. We were investigated of problems in application of structured analysis methods those journal articles that including statistical analysis techniques and analysis methods. Results : 1. A random allocation of the experimental group and control groups are important factors in the planning process of statistical analysis. However, there are less explanation those journal articles. 2. There are no consideration in specimen size that there will be considerate by the level of significance and statistical test. 3. Many article authors were confused between parametric methods and non-parametric methods that they were applied parametric statistical analysis methods although inapplicable sample size. 4. There were applied the parametric methods consists of t-test instead non-parametric methods in the comparison of average intergroup relations. 5. There were less understanding posterior analysis and were confused with t-test. Conclusion : Our goal was to outline the key methods with a brief discussion of problems(statistical analysis methods), avenues for solutions. we recommend authors to use an appropriate statistical analysis methods for obtaining a more cautions results.

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Variability of Short Term Creep Rupture Time and Life Prediction in Stainless Steels (스테인리스 강의 단시간 크리프 파단시간의 변동성과 수명예측)

  • Jung, Won-Taek;Kong, Yu-Sik;Kim, Seon-Jin
    • Journal of Ocean Engineering and Technology
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    • v.24 no.6
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    • pp.97-102
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    • 2010
  • This paper deals with the variability of short term creep rupture time based on previous creep rupture tests and the statistical methodology of the creep life prediction. The results of creep tests performed using constant uniaxial stresses at 600, 650, and $700^{\circ}C$ elevated temperatures were used for a statistical analysis of the inter-specimen variability of the short term creep rupture time. Even under carefully controlled identical testing conditions, the observed short-term creep rupture time showed obvious inter-specimen variability. The statistical aspect of the short term creep rupture time was analyzed using a Weibull statistical analysis. The effect of creep stress on the variability of the creep rupture time was decreased with an increase in the stress level. The effect of the temperature on the variability also decreased with increasing temperature. A long term creep life prediction method that considers this statistical variability is presented. The presented method is in good agreement with the Lason-Miller Parameter (LMP) life prediction method.

Statistical disclosure control for public microdata: present and future (마이크로데이터 공표를 위한 통계적 노출제어 방법론 고찰)

  • Park, Min-Jeong;Kim, Hang J.
    • The Korean Journal of Applied Statistics
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    • v.29 no.6
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    • pp.1041-1059
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    • 2016
  • The increasing demand from researchers and policy makers for microdata has also increased related privacy and security concerns. During the past two decades, a large volume of literature on statistical disclosure control (SDC) has been published in international journals. This review paper introduces relatively recent SDC approaches to the communities of Korean statisticians and statistical agencies. In addition to the traditional masking techniques (such as microaggregation and noise addition), we introduce an online analytic system, differential privacy, and synthetic data. For each approach, the application example (with pros and cons, as well as methodology) is highlighted, so that the paper can assist statical agencies that seek a practical SDC approach.

Prospects and Challenges of Social Media Marketing: Study of Indian Management Institutes

  • Bhandari, Ravneet Singh;Bansal, Sanjeev
    • Asian Journal of Business Environment
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    • v.8 no.4
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    • pp.5-15
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    • 2018
  • Purpose - The research aimed to reveal real decisional behavioral of management institutes in India for social media marketing usage, and analyses of empirical elements of social media consumption pattern. Research design, data, and methodology - The investigation was based around a research methodology using quantitative analysis with appropriate statistical techniques on random surveys of consumers, detailed exploratory and confirmatory factor analyses are applied to assess the empirical validity of the model and multiple regression employed using R studio edition to validate the reliability of the developed models. Results - A new conceptual framework is proposed - the management institutions decision model, providing a tool for effective and more focused decision-making strategies for developing better utilization techniques for social media. Management institutions have different requirements based upon objectives and resources available. The evidence suggests that the administrators need to be more aware of consumer indicators when targeting and designing social media marketing strategy. Conclusions - The research was based on samples and not the entire population of target consumers, providing limitations. As an inferential statistical method was chosen, the results might be susceptible to inaccuracy. The model developed from different age users, thereby providing rich perspectives into social media usage pattern.

Cost effective optimal mix proportioning of high strength self compacting concrete using response surface methodology

  • Khan, Asaduzzaman;Do, Jeongyun;Kim, Dookie
    • Computers and Concrete
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    • v.17 no.5
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    • pp.629-638
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    • 2016
  • Optimization of the concrete mixture design is a process of search for a mixture for which the sum of the cost of the ingredients is the lowest, yet satisfying the required performance of concrete. In this study, a statistical model was carried out to model a cost effective optimal mix proportioning of high strength self-compacting concrete (HSSCC) using the Response Surface Methodology (RSM). The effect of five key mixture parameters such as water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content on the properties and performance of HSSCC like compressive strength, passing ability, segregation resistance and manufacturing cost were investigated. To demonstrate the responses of model in quadratic manner Central Composite Design (CCD) was chosen. The statistical model showed the adjusted correlation coefficient R2adj values were 92.55%, 93.49%, 92.33%, and 100% for each performance which establish the adequacy of the model. The optimum combination was determined to be $439.4kg/m^3$ cement content, 35.5% W/B ratio, 50.0% fine aggregate, $49.85kg/m^3$ fly ash, and $7.76kg/m^3$ superplasticizer within the interest region using desirability function. Finally, it is concluded that multiobjective optimization method based on desirability function of the proposed response model offers an efficient approach regarding the HSSCC mixture optimization.

Statistical analysis and modelization of tool life and vibration in dry face milling of AISI 52100 STEEL in annealed and hardened conditions

  • Benghersallah, Mohieddine;Medjber, Ali;Zahaf, Mohamed Zakaria;Tibakh, Idriss;Amirat, Abdelaziz
    • Advances in materials Research
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    • v.9 no.3
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    • pp.189-202
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    • 2020
  • The objective of the present work is to investigate the effect of cutting parameters (Vc, fz and ap) on tool life and the level of vibrations velocity in the machined part during face milling operation of hardened AISI 52100 steel. Dry-face milling has been achieved in the annealed (28 HRc) and quenched (55 HRc) conditions using multi-layer coating micro-grain carbide inserts. Statistical analysis based on the Response surface methodology (RSM) and ANOVA analysis have been conducted through a plan of experiments methodology using a reduced Taguchi table (L9) in order to obtain engineering models for tool life and vibration velocity in the workpiece for both heat treatment conditions. The results show that the cutting speed has a dominant influence on tool life for both soft and hard part. Cutting speed and feed per tooth is the most significant parameters for vibration levels. Comparing the experimental values with those predicted by the developed engineering models of tool life and levels of vibrations velocity, a good correlation has been obtained (between 97% and 99%) in annealed and hard conditions.

Bayesian Variable Selection in the Proportional Hazard Model with Application to Microarray Data

  • Lee, Kyeong-Eun;Mallick, Bani K.
    • Proceedings of the Korean Statistical Society Conference
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    • 2005.05a
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    • pp.17-23
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    • 2005
  • In this paper we consider the well-known semiparametric proportional hazards models for survival analysis. These models are usually used with few covariates and many observations (subjects). But, for a typical setting of gene expression data from DNA microarray, we need to consider the case where the number of covariates p exceeds the number of samples n. For a given vector of response values which are times to event (death or censored times) and p gene expressions(covariates), we address the issue of how to reduce the dimension by selecting the significant genes. This approach enables us to estimate the survival curve when n ${\ll}$p. In our approach, rather than fixing the number of selected genes, we will assign a prior distribution to this number. The approach creates additional flexibility by allowing the imposition of constraints, such as bounding the dimension via a prior, which in effect works as a penalty To implement our methodology, we use a Markov Chain Monte Carlo (MCMC) method. We demonstrate the use of the methodology to diffuse large B-cell lymphoma (DLBCL) complementary DNA (cDNA) data and Breast Carcinomas data.

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Experimental analysis and modeling of steel fiber reinforced SCC using central composite design

  • Kandasamy, S.;Akila, P.
    • Computers and Concrete
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    • v.15 no.2
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    • pp.215-229
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    • 2015
  • The emerging technology of self compacting concrete, fiber reinforcement together reduces vibration and substitute conventional reinforcement which help in improving the economic efficiency of the construction. The objective of this work is to find the regression model to determine the response surface of mix proportioning Steel Fiber Reinforced Self Compacting Concrete (SFSCC) using statistical investigation. A total of 30 mixtures were designed and analyzed based on Design of Experiment (DOE). The fresh properties of SCC and mechanical properties of concrete were studied using Response Surface Methodology (RSM). The results were analyzed by limited proportion of fly ash, fiber, volume combination ratio of two steel fibers with aspect ratio of 50/35: 60/30 and super plasticizer (SP) dosage. The center composite designs (CCD) have selected to produce the response in quadratic equation. The model responses included in the primary stage were flowing ability, filling ability, passing ability and segregation index whereas in harden stage of concrete, compressive strength, split tensile strength and flexural strength at 28 days were tested. In this paper, the regression model and the response surface plots have been discussed, and optimal results were found for all the responses.

Assessment of Driver's Emotional Stability by Using Bio-signals (생체신호 측정을 통한 운전자의 감정적 안정상태 평가)

  • Kim, Jung-Yong;Park, Ji-Soo;Yoon, Sang-Young
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.1
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    • pp.203-211
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    • 2011
  • Objective: The aim of this study is to introduce a methodology to assess driver's emotion stability by using bio-signals. Background: Psychophysiological analysis of driver's behavior has been conducted to improve the driving safety and comfort. However, the variability of bio-signal and individual difference made it difficult to assess the psychophysiological status of drivers that can be expressed as emotional stability of drivers. Method: Two experimental studies were reviewed and summarized. New techniques assessing emotional stability of drivers were explained. Statistical concept and multidimensional space were used to identify the emotionally stable conditions. Conclusion: Psychophysiological approach can provide information of driver's emotional status. The experimental methodology and algorithm used in this study showed the possibility of parameterization of psychophysiological response. Application: Currently measured statistical and geometrical data can be further applied to develop an interactive device monitoring and reacting driver's emotion when driver experiences emotionally unstable or uncomfortable situation.