• Title/Summary/Keyword: Regression

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Hidden Truncation Normal Regression

  • Kim, Sungsu
    • Communications for Statistical Applications and Methods
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    • v.19 no.6
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    • pp.793-798
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    • 2012
  • In this paper, we propose regression methods based on the likelihood function. We assume Arnold-Beaver Skew Normal(ABSN) errors in a simple linear regression model. It was shown that the novel method performs better with an asymmetric data set compared to the usual regression model with the Gaussian errors. The utility of a novel method is demonstrated through simulation and real data sets.

Semisupervised support vector quantile regression

  • Seok, Kyungha
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.2
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    • pp.517-524
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    • 2015
  • Unlabeled examples are easier and less expensive to be obtained than labeled examples. In this paper semisupervised approach is used to utilize such examples in an effort to enhance the predictive performance of nonlinear quantile regression problems. We propose a semisupervised quantile regression method named semisupervised support vector quantile regression, which is based on support vector machine. A generalized approximate cross validation method is used to choose the hyper-parameters that affect the performance of estimator. The experimental results confirm the successful performance of the proposed S2SVQR.

REGRESSION WITH CENSORED DATA BY LEAST SQUARES SUPPORT VECTOR MACHINE

  • Kim, Dae-Hak;Shim, Joo-Yong;Oh, Kwang-Sik
    • Journal of the Korean Statistical Society
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    • v.33 no.1
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    • pp.25-34
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    • 2004
  • In this paper we propose a prediction method on the regression model with randomly censored observations of the training data set. The least squares support vector machine regression is applied for the regression function prediction by incorporating the weights assessed upon each observation in the optimization problem. Numerical examples are given to show the performance of the proposed prediction method.

Fuzzy Linear Regression with the Weakest t-norm

  • Lee, Sung-Ho;Kim, Kyung-Moo
    • Journal of the Korean Data and Information Science Society
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    • v.9 no.2
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    • pp.105-111
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    • 1998
  • In this paper a fuzzy regression model based on the weakest t-norm is introduced. The model shows a regression model which has fuzzy coefficients and fuzzy variables.

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Regression Estimators with Unequal Selection Probabilities on Two Successive Occasions

  • Kim, Kyu-Seong
    • Journal of the Korean Statistical Society
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    • v.25 no.1
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    • pp.25-37
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    • 1996
  • In this paper, we propose regression estimators based on a partial replacement sampling scheme over two successive occasions and derive the minimum variances of them. PPSWR, RHC, $\pi$PS and PPSWOR schemes are considered to select unequal probability samples on two occasions. Simulation results over four populations are given for comparison of composite estimators and regression estimators.

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A New Deletion Criterion of Principal Components Regression with Orientations of the Parameters

  • Lee, Won-Woo
    • Journal of the Korean Statistical Society
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    • v.16 no.2
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    • pp.55-70
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    • 1987
  • The principal components regression is one of the substitues for least squares method when there exists multicollinearity in the multiple linear regression model. It is observed graphically that the performance of the principal components regression is strongly dependent upon the values of the parameters. Accordingly, a new deletion criterion which determines proper principal components to be deleted from the analysis is developed and its usefulness is checked by simulations.

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Graphical Diagnostics for Logistic Regression

  • Lee, Hak-Bae
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.05a
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    • pp.213-217
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    • 2003
  • In this paper we discuss graphical and diagnostic methods for logistic regression, in which the response is the number of successes in a fixed number of trials.

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Multivariate Analysis for Clinicians (임상의를 위한 다변량 분석의 실제)

  • Oh, Joo Han;Chung, Seok Won
    • Clinics in Shoulder and Elbow
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    • v.16 no.1
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    • pp.63-72
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    • 2013
  • In medical research, multivariate analysis, especially multiple regression analysis, is used to analyze the influence of multiple variables on the result. Multiple regression analysis should include variables in the model and the problem of multi-collinearity as there are many variables as well as the basic assumption of regression analysis. The multiple regression model is expressed as the coefficient of determination, $R^2$ and the influence of independent variables on result as a regression coefficient, ${\beta}$. Multiple regression analysis can be divided into multiple linear regression analysis, multiple logistic regression analysis, and Cox regression analysis according to the type of dependent variables (continuous variable, categorical variable (binary logit), and state variable, respectively), and the influence of variables on the result is evaluated by regression coefficient${\beta}$, odds ratio, and hazard ratio, respectively. The knowledge of multivariate analysis enables clinicians to analyze the result accurately and to design the further research efficiently.

Comparison of Genetic Parameter Estimates of Total Sperm Cells of Boars between Random Regression and Multiple Trait Animal Models

  • Oh, S.-H.;See, M.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.7
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    • pp.923-927
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    • 2008
  • The objective of this study was to compare random regression model and multiple trait animal model estimates of the (co) variance of total sperm cells over the active lifetime of AI boars. Data were provided by Smithfield Premium Genetics (Rose Hill, NC). Total number of records and animals for the random regression model were 19,629 and 1,736, respectively. Data for multiple trait animal model analyses were edited to include only records produced at 9, 12, 15, 18, 21, 24, and 27 months of age. For the multiple trait method estimates of genetic and residual variance for total sperm cells were heterogeneous among age classifications. When comparing multiple trait method to random regression, heritability estimates were similar except for total sperm cells at 24 months of age. The multiple trait method also resulted in higher estimates of heritability of total sperm cells at every age when compared to random regression results. Random regression analysis provided more detail with regard to changes of variance components with age. Random regression methods are the most appropriate to analyze semen traits as they are longitudinal data measured over the lifetime of boars.