• 제목/요약/키워드: Selection methods

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지하구조물의 공법선정을 위한 요인분석 (Analysis of Factors for Selecting Construction Methods for Underground Structures)

  • 강현정;임홍철;박상현;이강
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2007년도 춘계학술논문 발표대회
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    • pp.37-40
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    • 2007
  • As a demand for underground structure is increasing with more parking and retail spaces required. Various construction methods are reviewed and selected for each specific site for economical and fast construction. In this study, factors for selecting construction methods were categorized for substructure construction. Construction processes of substructure are consisted of methods for excavation, earth retaining systems, and placement of slabs. Factors for the selection of substructure construction method are the condition of surrounding, geotechnical, information and constraint by comfortness for others nearby. After survey for the construction data of 5 different sites, analysis about reliable substructure construction selection method was suggested.

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Variable Selection in Sliced Inverse Regression Using Generalized Eigenvalue Problem with Penalties

  • Park, Chong-Sun
    • Communications for Statistical Applications and Methods
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    • 제14권1호
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    • pp.215-227
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    • 2007
  • Variable selection algorithm for Sliced Inverse Regression using penalty function is proposed. We noted SIR models can be expressed as generalized eigenvalue decompositions and incorporated penalty functions on them. We found from small simulation that the HARD penalty function seems to be the best in preserving original directions compared with other well-known penalty functions. Also it turned out to be effective in forcing coefficient estimates zero for irrelevant predictors in regression analysis. Results from illustrative examples of simulated and real data sets will be provided.

Local Bandwidth Selection for Nonparametric Regression

  • Lee, Seong-Woo;Cha, Kyung-Joon
    • Communications for Statistical Applications and Methods
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    • 제4권2호
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    • pp.453-463
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    • 1997
  • Nonparametric kernel regression has recently gained widespread acceptance as an attractive method for the nonparametric estimation of the mean function from noisy regression data. Also, the practical implementation of kernel method is enhanced by the availability of reliable rule for automatic selection of the bandwidth. In this article, we propose a method for automatic selection of the bandwidth that minimizes the asymptotic mean square error. Then, the estimated bandwidth by the proposed method is compared with the theoretical optimal bandwidth and a bandwidth by plug-in method. Simulation study is performed and shows satisfactory behavior of the proposed method.

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Efficient Controlled Selection

  • Ryu, Jea-Bok;Lee, Seung-Joo
    • Communications for Statistical Applications and Methods
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    • 제4권1호
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    • pp.151-159
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    • 1997
  • In sample surveys, we expect preferred samples that reduce the survey cost and increase the precision of estimators will be selected. Goodman and Kish (1950) introduced controlled selection as a method of sample selection that increases the probability of drawing preferred samples, while decreases the probability of drawing nonpreferred samples. In this paper, we obtain the controlled plans using the maximum entropy principle, and when the order of nonpreferred samples is considered, we propose the algorithm to obtain a controlled plan.

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Bias Reduction in Split Variable Selection in C4.5

  • Shin, Sung-Chul;Jeong, Yeon-Joo;Song, Moon Sup
    • Communications for Statistical Applications and Methods
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    • 제10권3호
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    • pp.627-635
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    • 2003
  • In this short communication we discuss the bias problem of C4.5 in split variable selection and suggest a method to reduce the variable selection bias among categorical predictor variables. A penalty proportional to the number of categories is applied to the splitting criterion gain of C4.5. The results of empirical comparisons show that the proposed modification of C4.5 reduces the size of classification trees.

Selection of Data-adaptive Polynomial Order in Local Polynomial Nonparametric Regression

  • Jo, Jae-Keun
    • Communications for Statistical Applications and Methods
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    • 제4권1호
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    • pp.177-183
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    • 1997
  • A data-adaptive order selection procedure is proposed for local polynomial nonparametric regression. For each given polynomial order, bias and variance are estimated and the adaptive polynomial order that has the smallest estimated mean squared error is selected locally at each location point. To estimate mean squared error, empirical bias estimate of Ruppert (1995) and local polynomial variance estimate of Ruppert, Wand, Wand, Holst and Hossjer (1995) are used. Since the proposed method does not require fitting polynomial model of order higher than the model order, it is simpler than the order selection method proposed by Fan and Gijbels (1995b).

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작업 일정계획문제 해결을 위한 유전알고리듬의 응용 (Application of Genetic Algorithms to a Job Scheduling Problem)

  • 김석준;이채영
    • 한국경영과학회지
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    • 제17권3호
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    • pp.1-12
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    • 1992
  • Parallel Genetic Algorithms (GAs) are developed to solve a single machine n-job scheduling problem which is to minimize the sum of absolute deviations of completion times from a common due date. (0, 1) binary scheme is employed to represent the n-job schedule. Two selection methods, best individual selection and simple selection are examined. The effect of crossover operator, due date adjustment mutation and due date adjustment reordering are discussed. The performance of the parallel genetic algorithm is illustrated with some example problems.

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Bandwidth Selection for Local Smoothing Jump Detector

  • Park, Dong-Ryeon
    • Communications for Statistical Applications and Methods
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    • 제16권6호
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    • pp.1047-1054
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    • 2009
  • Local smoothing jump detection procedure is a popular method for detecting jump locations and the performance of the jump detector heavily depends on the choice of the bandwidth. However, little work has been done on this issue. In this paper, we propose the bootstrap bandwidth selection method which can be used for any kernel-based or local polynomial-based jump detector. The proposed bandwidth selection method is fully data-adaptive and its performance is evaluated through a simulation study and a real data example.

Language- Independent Sentence Boundary Detection with Automatic Feature Selection

  • Lee, Do-Gil
    • Journal of the Korean Data and Information Science Society
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    • 제19권4호
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    • pp.1297-1304
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    • 2008
  • This paper proposes a machine learning approach for language-independent sentence boundary detection. The proposed method requires no heuristic rules and language-specific features, such as part-of-speech information, a list of abbreviations or proper names. With only the language-independent features, we perform experiments on not only an inflectional language but also an agglutinative language, having fairly different characteristics (in this paper, English and Korean, respectively). In addition, we obtain good performances in both languages. We have also experimented with the methods under a wide range of experimental conditions, especially for the selection of useful features.

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Nonparametric Selection Procedures and Their Efficiency Comparisons

  • Sohn, Joong-K.;Shanti S.Gupta;Kim, Heon-Joo
    • Communications for Statistical Applications and Methods
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    • 제1권1호
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    • pp.41-51
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    • 1994
  • We consider nonparametric procedures for the selection and ranking problems. Tukey's generalized lambda distribution is condidered as the distribution for the score function because the distribution can approximate many well-known contionuous distributions. Also we compare these procedures in terms of efficiency, defined by the ratio of a probability of a correct selection divided by the expected selected subset size.

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