• Title/Summary/Keyword: statistical techniques

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Optimization Methodology Integrated Data Mining and Statistical Method (데이터 마이닝과 통계적 기법을 통합한 최적화 기법)

  • Song, Suh-Ill;Shin, Sang-Mun;Jung, Hey-Jin
    • Journal of Korean Society for Quality Management
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    • v.34 no.4
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    • pp.33-39
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    • 2006
  • These days manufacture technology and manufacture environment are changing rapidly. By development of computer and enlargement of technique, most of manufacture field are computerized. In order to win international competition, it is important for companies how fast get the useful information from vast data. Statistical process control(SPC) techniques have been used as a problem solution tool at manufacturing process until present. However, these statistical methods are not applied more extensively because it has much restrictions in realistic problems. These statistical techniques have lots of problems when much data and factors are analyzed. In this paper, we proposed more practical and efficient a new statistical design technique which integrated data mining (DM) and statistical methods as alternative of problems. First step is selecting significant factor using DM feature selection algorithm from data of manufacturing process including many factors. Second step is finding optimum of process after estimating response function through response surface methodology(RSM) that is a statistical techniques

Statistical Techniques for Automatic Indexing and Some Experiments with Korean Documents (자동색인의 통계적기법과 한국어 문헌의 실험)

  • Chung Young Mee;Lee Tae Young
    • Journal of the Korean Society for Library and Information Science
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    • v.9
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    • pp.99-118
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    • 1982
  • This paper first reviews various techniques proposed for automatic indexing with special emphasis placed on statistical techniques. Frequency-based statistical techniques are categorized into the following three approaches for further investigation on the basis of index term selection criteria: term frequency approach, document frequency approach, and probabilistic approach. In the experimental part of this study, Pao's technique based on the Goffman's transition region formula and Harter's 2-Poisson distribution model with a measure of the potential effectiveness of index term were tested. Experimental document collection consists of 30 agriculture-related documents written in Korean. Pao's technique did not yield good result presumably due to the difference in word usage between Korean and English. However, Harter's model holds some promise for Korean document indexing because the evaluation result from this experiment was similar to that of the Harter's.

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Statistical Error Compensation Techniques for Spectral Quantization

  • Choi, Seung-Ho;Kim, Hong-Kook
    • Speech Sciences
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    • v.11 no.4
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    • pp.17-28
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    • 2004
  • In this paper, we propose a statistical approach to improve the performance of spectral quantization of speech coders. The proposed techniques compensate for the distortion in a decoded line spectrum pairs (LSP) vector based on a statistical mapping function between a decoded LSP vector and its corresponding original LSP vector. We first develop two codebook-based probabilistic matching (CBPM) methods based on linear mapping functions according to different assumption of distribution of LSP vectors. In addition, we propose an iterative procedure for the two CBPMs. We apply the proposed techniques to a predictive vector quantizer used for the IS-641 speech coder. The experimental results show that the proposed techniques reduce average spectral distortion by around 0.064dB.

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Structural Equation Modeling Using R: Mediation/Moderation Effect Analysis and Multiple-Group Analysis (R을 이용한 구조방정식모델링: 매개효과분석/조절효과분석 및 다중집단분석)

  • Kwahk, Kee-Young
    • Knowledge Management Research
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    • v.20 no.2
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    • pp.1-24
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    • 2019
  • This tutorial introduces procedures and methods for performing structural equation modeling using R. To do this, we present advanced analysis methods based on structural equation model such as mediation effect analysis, moderation effect analysis, moderated mediation effect analysis, and multiple-group analysis with R program code using R lavaan package that supports structural equation modeling. R is flexible and scalable, unlike traditional commercial statistical packages. Therefore, new analytical techniques are likely to be implemented ahead of any other statistical package. From this point of view, R will be a very appropriate choice for applying new analytical techniques or advanced techniques that researchers need. Considering that various studies in the social sciences are applying structural equations modeling techniques and increasing interest in open source R, this tutorial is expected to be useful for researchers who are looking for alternatives to existing commercial statistical packages.

STATISTICAL CONCEPTS AND TECHNIQUES FOR TESTING DEPARTURES FROM NORMALITY IN THE MATHEMATICS TEACHER PREPARATION

  • Lee, Sang-Gone
    • Honam Mathematical Journal
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    • v.29 no.1
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    • pp.83-100
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    • 2007
  • Normality is one of the most common assumptions made in sampling and statistical inference procedures without suffering from lack of attention. Its results may lead to an invalid conclusion. We present several testing procedures that can be used to evaluate the effects of departure from normality using concrete examples by hand or with the aid of Minitab. The goal is to influence prospective teachers in order to learn statistical concepts and techniques for testing normality on the basis of the didactical theory.

Pooling-Across-Environments Method for the Generation of Composite-Material Allowables (환경조건간 합동을 이용한 복합재료 허용치 생성 기법)

  • Rhee, Seung Yun
    • Journal of Aerospace System Engineering
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    • v.10 no.3
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    • pp.63-69
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    • 2016
  • The properties of composite materials, when compared to those of metallic materials, are highly variable due to many factors including the batch-to-batch variability of raw materials, the prepreg manufacturing process, material handling, part-fabrication techniques, ply-stacking sequences, environmental conditions, and test procedures. It is therefore necessary to apply reliable statistical-analysis techniques to obtain the design allowables of composite materials. A new composite-material qualification process has been developed by the Advanced General Aviation Transport Experiments (AGATE) consortium to yield the lamina-design allowables of composite materials according to standardized coupon-level tests and statistical techniques; moreover, the generated allowables database can be shared among multiple users without a repeating of the full qualification procedure by each user. In 2005, NASA established the National Center for Advanced Materials Performance (NCAMP) with the purpose of refining and enhancing the AGATE process to a self-sustaining level to serve the entire aerospace industry. In this paper, the statistical techniques and procedures for the generation of the allowables of aerospace composite materials will be discussed with a focus on the pooling-across-environments method.

Periodization in the History of Statistics

  • Jo, Jae-Keun
    • Communications for Statistical Applications and Methods
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    • v.11 no.1
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    • pp.31-47
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    • 2004
  • The history of statistics from the mid-seventeenth to the early twentieth century is considered and a scheme of periodization is proposed. In the first period(1650-1750), named 'the age of probability' in this paper, concept of probability emerged, and in the second period(1750-1820), named 'the age of error theory', statistical techniques such as the least square method are developed by astronomers and geodesists. Their techniques are supported theoretically by mathematicians like Laplace and Gauss in that period. The third period(1820-1880) is called 'the age of statistics(as a plural noun)' since statistical data played prominent roles in social sciences such as sociology, psychology. Finally the last period(1880- ), called 'the age of statistics(as a singular noun)', the discipline of statistics came to maturity both in theory and application.

A Historical Study on Statistical Packages in Cluster Analysis

  • 이승우
    • Journal for History of Mathematics
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    • v.11 no.1
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    • pp.52-57
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    • 1998
  • Since cluster analysis encompasses many diverse techniques for discovering structure within complex bodies of data, it has been employed as an effective tool in scientific inquiry. Recent works on cluster analysis softwares carried out by SAS, SPSS, S-PLUS and BMDP are briefly summarized and investigated in this paper. The inferred statistical package for windows executing a nay for data analysis in modern statistical techniques has several merits superior to other packages. Especially, S-PLUS can be designed and tried out much faster than other statistical packages. S-PLUS provides a graphic which is interactive, informative, flexible ways of looking at data. Also, if a statistical computation time is long and programs are complex, these can be shorten by providing interfaces to the UNIX systems (or C, Fortran).

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