• 제목/요약/키워드: Linear Regression

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Comparison of Confidence Intervals on Variance Component In a Simple Linear Regression Model with Unbalanced Nested Error Structure

  • Park, Dong Joon;Park, Sun-Young;Han, Man-Ho
    • Communications for Statistical Applications and Methods
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    • 제9권2호
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    • pp.459-471
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    • 2002
  • In applications using a linear regression model with nested error structure, one might be interested in making inferences concerning variance components. This article proposes approximate confidence intervals on the variance component of the primary level in a simple linear regression model with an unbalanced nested error structure. The intervals are compared using computer simulation and recommendations are provided for selecting an appropriate interval.

Consistency and Bounds on the Bias of $S^2$ in the Linear Regression Model with Moving Average Disturbances

  • Song, Seuck-Heun
    • Journal of the Korean Statistical Society
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    • 제24권2호
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    • pp.507-518
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    • 1995
  • The ordinary least squares based estiamte $S^2$ of the disturbance variance is considered in the linear regression model when the disturbances follow the first-order moving-average process. It is shown that $S^2$ is weakly consistent estimate for the disturbance varaince without any restriction on the regressor matrix X. Also, simple exact bounds on the relative bias of $S^2$ are given in finite sample sizes.

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ON MARGINAL INTEGRATION METHOD IN NONPARAMETRIC REGRESSION

  • Lee, Young-Kyung
    • Journal of the Korean Statistical Society
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    • 제33권4호
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    • pp.435-447
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    • 2004
  • In additive nonparametric regression, Linton and Nielsen (1995) showed that the marginal integration when applied to the local linear smoother produces a rate-optimal estimator of each univariate component function for the case where the dimension of the predictor is two. In this paper we give new formulas for the bias and variance of the marginal integration regression estimators which are valid for boundary areas as well as fixed interior points, and show the local linear marginal integration estimator is in fact rate-optimal when the dimension of the predictor is less than or equal to four. We extend the results to the case of the local polynomial smoother, too.

段階的 多變量 線型回歸에 관하여 (Alternative Derivation of Stepwise Multivariate Linear Regression)

  • 申敏雄;金周成
    • Journal of the Korean Statistical Society
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    • 제7권2호
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    • pp.105-108
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    • 1978
  • Freund, Vail, and Ross, Goldberger and Jochems and Goldberger have given some results for the stepwise estimation of the parameters of a univariate regression model, D.G. Kabe gave similar results for a multivariate linear regression model. We give here alternative derivation of some results derived by D.G. Kabe.

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A Technique to Improve the Fit of Linear Regression Models for Successive Sets of Data

  • Park, Sung H.
    • Journal of the Korean Statistical Society
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    • 제5권1호
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    • pp.19-28
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    • 1976
  • In empirical study for fitting a multiple linear regression model for successive cross-sections data observed on the same set of independent variables over several time periods, one often faces the problem of poor $R^2$, the multiple coefficient of determination, which provides a standard measure of how good a specified regression line fits the sample data.

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INFLUENCE ANALYSIS FOR A LINEAR HYPOTHESIS IN MULTIVARIATE REGRESSION MODEL

  • Kim, Myung-Geun
    • Journal of applied mathematics & informatics
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    • 제13권1_2호
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    • pp.479-485
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    • 2003
  • The influence of observations on the Wilks' lambda test of a linear hypothesis in multivariate regression is investigated using the local influence method. The perturbation scheme of case-weights is considered. A numerical example is given to show the effectiveness of the local influence method in identifying the influential observations.

선형계통의 파라미터 추정을 위한 최적 입력의 설계 (Design of the optimal inputs for parameter estimation in linear dynamic systems)

  • 양흥석;이석원;정찬수
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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    • pp.73-77
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    • 1986
  • Optimal input design problem for linear regression model with constrained output variance has been considered. It is shown that the optimal input signal for the linear regression model can also be realized as an ARMA process. Monte-Carlo simulation results show that the optimal stochastic input leads to comparatively better estimation accuracy than white input signal.

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Comparison of linear and non-linear equation for the calibration of roxithromycin analysis using liquid chromatography/mass spectrometry

  • Lim, Jong-Hwan;Yun, Hyo-In
    • 대한수의학회지
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    • 제50권1호
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    • pp.11-17
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    • 2010
  • Linear and non-linear regressions were used to derive the calibration function for the measurement of roxithromycin plasma concentration. Their results were compared with weighted least squares regression by usual weight factors. In this paper the performance of a non-linear calibration equation with the capacity to account empirically for the curvature, y = ax$^{b}$ + c (b $\neq$ 1) is compared with the commonly used linear equation, y = ax + b, as well as the quadratic equation, y = ax$^{2}$+ bx + c. In the calibration curve (range of 0.01 to 10 ${\mu}g/mL$) of roxithromycin, both heteroscedasticity and nonlinearity were present therefore linear least squares regression methods could result in large errors in the determination of roxithromycin concentration. By the non-linear and weighted least squares regression, the accuracy of the analytical method was improved at the lower end of the calibration curve. This study suggests that the non-linear calibration equation should be considered when a curve is required to be fitted to low dose calibration data which exhibit slight curvature.

Bayesian Estimation for the Multiple Regression with Censored Data : Mutivariate Normal Error Terms

  • Yoon, Yong-Hwa
    • Journal of the Korean Data and Information Science Society
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    • 제9권2호
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    • pp.165-172
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    • 1998
  • This paper considers a linear regression model with censored data where each error term follows a multivariate normal distribution. In this paper we consider the diffuse prior distribution for parameters of the linear regression model. With censored data we derive the full conditional densities for parameters of a multiple regression model in order to obtain the marginal posterior densities of the relevant parameters through the Gibbs Sampler, which was proposed by Geman and Geman(1984) and utilized by Gelfand and Smith(1990) with statistical viewpoint.

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Change-Points with Jump in Nonparametric Regression Functions

  • Kim, Jong-Tae
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2005년도 춘계학술대회
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    • pp.193-199
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    • 2005
  • A simple method is proposed to detect the number of change points with jump discontinuities in nonparamteric regression functions. The proposed estimators are based on a local linear regression fit by the comparison of left and right one-side kernel smoother. Also, the proposed methodology is suggested as the test statistic for detecting of change points and the direction of jump discontinuities.

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