• Title/Summary/Keyword: Regression

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DETECTION OF OUTLIERS IN WEIGHTED LEAST SQUARES REGRESSION

  • Shon, Bang-Yong;Kim, Guk-Boh
    • Journal of applied mathematics & informatics
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    • v.4 no.2
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    • pp.501-512
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    • 1997
  • In multiple linear regression model we have presupposed assumptions (independence normality variance homogeneity and so on) on error term. When case weights are given because of variance heterogeneity we can estimate efficiently regression parameter using weighted least squares estimator. Unfortunately this estimator is sen-sitive to outliers like ordinary least squares estimator. Thus in this paper we proposed some statistics for detection of outliers in weighted least squares regression.

Regression Quantiles Under Censoring and Truncation

  • Park, Jin-Ho;Kim, Jin-Mi
    • Communications for Statistical Applications and Methods
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    • v.12 no.3
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    • pp.807-818
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    • 2005
  • In this paper we propose an estimation method for regression quantiles with left-truncated and right-censored data. The estimation procedure is based on the weight determined by the Kaplan-Meier estimate of the distribution of the response. We show how the proposed regression quantile estimators perform through analyses of Stanford heart transplant data and AIDS incubation data. We also investigate the effect of censoring on regression quantiles through simulation study.

Polynomial Boundary Treatment for Wavelet Regression

  • Oh Hee-Seok;Naveau Philppe;Lee GeungHee
    • Proceedings of the Korean Statistical Society Conference
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    • 2000.11a
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    • pp.27-32
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    • 2000
  • To overcome boundary problems with wavelet regression, we propose a simple method that reduces bias at the boundaries. It is based on a combination of wavelet functions and low-order polynomials. The utility of the method is illustrated with simulation studies and a real example. Asymptotic results show that the estimators are competitive with other nonparametric procedures.

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On Confidence Intervals of High Breakdown Regression Estimators

  • Lee Dong-Hee;Park YouSung;Kim Kang-yong
    • Proceedings of the Korean Statistical Society Conference
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    • 2004.11a
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    • pp.205-210
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    • 2004
  • A weighted self-tuning robust regression estimator (WSTE) has the high breakdown point for estimating regression parameters such as other well known high breakdown estimators. In this paper, we propose to obtain standard quantities like confidence intervals, and it is found to be superior to the other high breakdown regression estimators when a sample is contaminated

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Weighted LS-SVM Regression for Right Censored Data

  • Kim, Dae-Hak;Jeong, Hyeong-Chul
    • Communications for Statistical Applications and Methods
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    • v.13 no.3
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    • pp.765-776
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    • 2006
  • In this paper we propose an estimation method on the regression model with randomly censored observations of the training data set. The weighted least squares support vector machine regression is applied for the regression function estimation by incorporating the weights assessed upon each observation in the optimization problem. Numerical examples are given to show the performance of the proposed estimation method.

THE STRONG CONSISTENCY OF NONLINEAR REGRESSION QUANTILES ESTIMATORS

  • Choi, Seung-Hoe;Kim, Hae-Kyung
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.3
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    • pp.451-457
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    • 1999
  • This paper provides sufficient conditions which ensure the strong consistency of regression quantiles estimators of nonlinear regression models. The main result is supported by the application of an asymptotic property of the least absolute deviation estimators as a special case of the proposed estimators. some example is given to illustrate the application of the main result.

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Self-tuning Robust Regression Estimation

  • Park, You-Sung;Lee, Dong-Hee
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.10a
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    • pp.257-262
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    • 2003
  • We introduce a new robust regression estimator, self-tuning regression estimator. Various robust estimators have been developed with discovery for theories and applications since Huber introduced M-estimator at 1960's. We start by announcing various robust estimators and their properties, including their advantages and disadvantages, and furthermore, new estimator overcomes drawbacks of other robust regression estimators, such as ineffective computation on preserving robustness properties.

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Kernel Poisson regression for mixed input variables

  • Shim, Jooyong
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.6
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    • pp.1231-1239
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    • 2012
  • An estimating procedure is introduced for kernel Poisson regression when the input variables consist of numerical and categorical variables, which is based on the penalized negative log-likelihood and the component-wise product of two different types of kernel functions. The proposed procedure provides the estimates of the mean function of the response variables, where the canonical parameter is linearly and/or nonlinearly related to the input variables. Experimental results are then presented which indicate the performance of the proposed kernel Poisson regression.

Fuzzy regression using regularlization method based on Tanaka's model

  • Hong Dug-Hun;Kim Kyung-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.16 no.4
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    • pp.499-505
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    • 2006
  • Regularlization approach to regression can be easily found in Statistics and Information Science literature. The technique of regularlization was introduced as a way of controlling the smoothness properties of regression function. In this paper, we have presented a new method to evaluate linear and non-linear fuzzy regression model based on Tanaka's model using the idea of regularlization technique. Especially this method is a very attractive approach to model non -linear fuzzy data.

Imputation Procedures in Weibull Regression Analysis in the presence of missing values

  • Kim Soon-kwi;Jeong Bong-Bin
    • Proceedings of the Korean Statistical Society Conference
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    • 2001.11a
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    • pp.143-148
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    • 2001
  • A dataset having missing observations is often completed by using imputed values. In this paper the performances and accuracy of complete case methods and four imputation procedures are evaluated when missing values exist only on the response variables in the Weibull regression model. Our simulation results show that compared to other imputation procedures, in particular, hotdeck and Weibull regression imputation procedure can be well used to compensate for missing data. In addition an illustrative real data is given.

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