Log in

Relevant bibliographies by topics / Tilted Local Linear Estimator / Journal articles

Journal articles on the topic 'Tilted Local Linear Estimator'

To see the other types of publications on this topic, follow the link: Tilted Local Linear Estimator.

Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Tilted Local Linear Estimator.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Cohen, Israel, Nicholas Coult, and Anthony A. Vassiliou. "Detection and extraction of fault surfaces in 3D seismic data." GEOPHYSICS 71, no. 4 (July 2006): P21—P27. http://dx.doi.org/10.1190/1.2215357.

Full text

Abstract:

We propose an efficient method for detecting and extracting fault surfaces in 3D-seismic volumes. The seismic data are transformed into a volume of local-fault-extraction (LFE) estimates that represents the likelihood that a given point lies on a fault surface. We partition the fault surfaces into relatively small linear portions, which are identified by analyzing tilted and rotated subvolumes throughout the region of interest. Directional filtering and thresholding further enhance the seismic discontinuities that are attributable to fault surfaces. Subsequently, the volume of LFE estimates is skeletonized, and individual fault surfaces are extracted and labeled in the order of decreasing size. The ultimate result obtained by the proposed procedure provides a visual and semantic representation of a set of well-defined, cleanly separated, one-pixel-thick, labeled fault surfaces that is readily usable for seismic interpretation.

APA, Harvard, Vancouver, ISO, and other styles

2

Wang, Shuguang, and Adam H. Sobel. "A Unified Moisture Mode Theory for the Madden–Julian Oscillation and the Boreal Summer Intraseasonal Oscillation." Journal of Climate 35, no. 4 (February 15, 2022): 1267–91. http://dx.doi.org/10.1175/jcli-d-21-0361.1.

Full text

Abstract:

Abstract The Madden–Julian oscillation (MJO) and the boreal summer intraseasonal oscillation (BSISO) are fundamental modes of variability in the tropical atmosphere on the intraseasonal time scale. A linear model, using a moist shallow water equation set on an equatorial beta plane, is developed to provide a unified treatment of the two modes and to understand their growth and propagation over the Indian Ocean. Moisture is assumed to increase linearly with longitude and to decrease quadratically with latitude. Solutions are obtained through linear stability analysis, considering the gravest (n = 1) meridional mode with nonzero meridional velocity. Anomalies in zonal moisture advection and surface fluxes are both proportional to those in zonal wind, but of opposite sign. With observation-based estimates for both effects, the zonal advection dominates, and drives the planetary-scale instability. With a sufficiently small meridional moisture gradient, the horizontal structure exhibits oscillations with latitude and a northwest–southeast horizontal tilt in the Northern Hemisphere, qualitatively resembling the observed BSISO. As the meridional moisture gradient increases, the horizontal tilt decreases and the spatial pattern transforms toward the “swallowtail” structure associated with the MJO, with cyclonic gyres in both hemispheres straddling the equatorial precipitation maximum. These results suggest that the magnitude of the meridional moisture gradient shapes the horizontal structures, leading to the transformation from the BSISO-like tilted horizontal structure to the MJO-like neutral wave structure as the meridional moisture gradient changes with the seasons. The existence and behavior of these intraseasonal modes can be understood as a consequence of phase speed matching between the equatorial mode with zero meridional velocity (analogous to the dry Kelvin wave) and a local off-equatorial component that is characterized by considering an otherwise similar system on an f plane.

APA, Harvard, Vancouver, ISO, and other styles

3

CAMASSA, ROBERTO, RICHARD M. McLAUGHLIN, and LONGHUA ZHAO. "Lagrangian blocking in highly viscous shear flows past a sphere." Journal of Fluid Mechanics 669 (February 16, 2011): 120–66. http://dx.doi.org/10.1017/s0022112010004933.

Full text

Abstract:

An analytical and computational study of Lagrangian trajectories for linear shear flow past a sphere or spheroid at low Reynolds numbers is presented. Using the exact solutions available for the fluid flow in this geometry, we discover and analyse blocking phenomena, local bifurcation structures and their influence on dynamical effects arising in the fluid particle paths. In particular, building on the work by Chwang & Wu, who established an intriguing blocking phenomenon in two-dimensional flows, whereby a cylinder placed in a linear shear prevents an unbounded region of upstream fluid from passing the body, we show that a similar blocking exists in three-dimensional flows. For the special case when the sphere is centred on the zero-velocity plane of the background shear, the separatrix streamline surfaces which bound the blocked region are computable in closed form by quadrature. This allows estimation of the cross-sectional area of the blocked flow showing how the area transitions from finite to infinite values, depending on the cross-section location relative to the body. When the sphere is off-centre, the quadrature appears to be unavailable due to the broken up-down mirror symmetry. In this case, computations provide evidence for the persistence of the blocking region. Furthermore, we document a complex bifurcation structure in the particle trajectories as the sphere centre is moved from the zero-velocity plane of the background flow. We compute analytically the emergence of different fixed points in the flow and characterize the global streamline topology associated with these fixed points, which includes the emergence of a three-dimensional bounded eddy. Similar results for the case of spheroids are considered in Appendix B. Additionally, the broken symmetry offered by a tilted spheroid geometry induces new three-dimensional effects on streamline deflection, which can be viewed as effective positive or negative suction in the horizontal direction orthogonal to the background flow, depending on the tilt orientation. We conclude this study with results on the case of a sphere embedded at a generic position in a rotating background flow, with its own prescribed rotation including fixed and freely rotating. Exact closed-form solutions for fluid particle trajectories are derived.

APA, Harvard, Vancouver, ISO, and other styles

4

Ziegelmann, Flavio A. "NONPARAMETRIC ESTIMATION OF VOLATILITY FUNCTIONS: THE LOCAL EXPONENTIAL ESTIMATOR." Econometric Theory 18, no. 4 (May 17, 2002): 985–91. http://dx.doi.org/10.1017/s026646660218409x.

Full text

Abstract:

Kernel smoothing techniques free the traditional parametric estimators of volatility from the constraints related to their specific models. In this paper the nonparametric local exponential estimator is applied to estimate conditional volatility functions, ensuring its nonnegativity. Its asymptotic properties are established and compared with those for the local linear estimator. It theoretically enables us to determine when the exponential is expected to be superior to the linear estimator. A very strong and novel result is achieved: the exponential estimator is asymptotically fully adaptive to unknown conditional mean functions. Also, our simulation study shows superior performance of the exponential estimator.

APA, Harvard, Vancouver, ISO, and other styles

5

Kou, Junke, Qinmei Huang, and Huijun Guo. "Pointwise Wavelet Estimations for a Regression Model in Local Hölder Space." Axioms 11, no. 9 (September 10, 2022): 466. http://dx.doi.org/10.3390/axioms11090466.

Full text

Abstract:

This paper considers an unknown functional estimation problem in a regression model with multiplicative and additive noise. A linear wavelet estimator is first constructed by a wavelet projection operator. The convergence rate under the pointwise error of linear wavelet estimators is studied in local Hölder space. A nonlinear wavelet estimator is provided by the hard thresholding method in order to obtain an adaptive estimator. The convergence rate of the nonlinear estimator is the same as the linear estimator up to a logarithmic term. Finally, it should be pointed out that the convergence rates of two wavelet estimators are consistent with the optimal convergence rate on pointwise nonparametric estimation.

APA, Harvard, Vancouver, ISO, and other styles

6

Casas, Isabel, and Irene Gijbels. "Unstable volatility: the break-preserving local linear estimator." Journal of Nonparametric Statistics 24, no. 4 (December 2012): 883–904. http://dx.doi.org/10.1080/10485252.2012.720981.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Chan, Nigel, and Qiying Wang. "UNIFORM CONVERGENCE FOR NONPARAMETRIC ESTIMATORS WITH NONSTATIONARY DATA." Econometric Theory 30, no. 5 (April 25, 2014): 1110–33. http://dx.doi.org/10.1017/s026646661400005x.

Full text

Abstract:

Sharp upper and lower uniform bounds are established for a general class of functionals of integrated and fractionally integrated time series. The main result is used to develop optimal uniform convergence for the Nadaraya-Watson estimator and the local linear nonparametric estimator in a nonlinear cointegrating regression model. Unlike the point-wise situation, it is shown that the performance of the local linear nonparametric estimator is superior to that of the Nadaraya-Watson estimator in uniform asymptotics.

APA, Harvard, Vancouver, ISO, and other styles

8

Ziegelmann, Flavio A. "A Local Linear Least-Absolute-Deviations Estimator of Volatility." Communications in Statistics - Simulation and Computation 37, no. 8 (August 27, 2008): 1543–64. http://dx.doi.org/10.1080/03610910802244398.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Bouhadjera, Feriel, and Elias Ould Said. "Strong consistency of the local linear relative regression estimator for censored data." Opuscula Mathematica 42, no. 6 (2022): 805–32. http://dx.doi.org/10.7494/opmath.2022.42.6.805.

Full text

Abstract:

In this paper, we combine the local linear approach to the relative error regression estimation method to build a new estimator of the regression operator when the response variable is subject to random right censoring. We establish the uniform almost sure consistency with rate over a compact set of the proposed estimator. Numerical studies, firstly on simulated data, then on a real data set concerning the death times of kidney transplant patients, were conducted. These practical studies clearly show the superiority of the new estimator compared to competitive estimators.

APA, Harvard, Vancouver, ISO, and other styles

10

Kikechi, Conlet Biketi, and Richard Onyino Simwa. "On Comparison of Local Polynomial Regression Estimators for P=0 and P=1 in a Model Based Framework." International Journal of Statistics and Probability 7, no. 4 (June 27, 2018): 104. http://dx.doi.org/10.5539/ijsp.v7n4p104.

Full text

Abstract:

This article discusses the local polynomial regression estimator for and the local polynomial regression estimator for in a finite population. The performance criterion exploited in this study focuses on the efficiency of the finite population total estimators. Further, the discussion explores analytical comparisons between the two estimators with respect to asymptotic relative efficiency. In particular, asymptotic properties of the local polynomial regression estimator of finite population total for are derived in a model based framework. The results of the local polynomial regression estimator for are compared with those of the local polynomial regression estimator for studied by Kikechi et al (2018). Variance comparisons are made using the local polynomial regression estimator for and the local polynomial regression estimator for which indicate that the estimators are asymptotically equivalently efficient. Simulation experiments carried out show that the local polynomial regression estimator outperforms the local polynomial regression estimator in the linear, quadratic and bump populations.

APA, Harvard, Vancouver, ISO, and other styles

11

Zhang, Zhengyu. "LOCAL PARTITIONED QUANTILE REGRESSION." Econometric Theory 33, no. 5 (September 19, 2016): 1081–120. http://dx.doi.org/10.1017/s0266466616000293.

Full text

Abstract:

In this paper, we consider the nonparametric estimation of a broad class of quantile regression models, in which the partially linear, additive, and varying coefficient models are nested. We propose for the model a two-stage kernel-weighted least squares estimator by generalizing the idea of local partitioned mean regression (Christopeit and Hoderlein, 2006, Econometrica 74, 787–817) to a quantile regression framework. The proposed estimator is shown to have desirable asymptotic properties under standard regularity conditions. The new estimator has three advantages relative to existing methods. First, it is structurally simple and widely applicable to the general model as well as its submodels. Second, both the functional coefficients and their derivatives up to any given order can be estimated. Third, the procedure readily extends to censored data, including fixed or random censoring. A Monte Carlo experiment indicates that the proposed estimator performs well in finite samples. An empirical application is also provided.

APA, Harvard, Vancouver, ISO, and other styles

12

Almanjahie, Ibrahim M., Zoulikha Kaid, Ali Laksaci, and Mustapha Rachdi. "Estimating the Conditional Density in Scalar-On-Function Regression Structure: k-N-N Local Linear Approach." Mathematics 10, no. 6 (March 11, 2022): 902. http://dx.doi.org/10.3390/math10060902.

Full text

Abstract:

In this study, the problem of conditional density estimation of a scalar response variable, given a functional covariable, is considered. A new estimator is proposed by combining the k-nearest neighbors (k-N-N) procedure with the local linear approach. Then, the uniform consistency in the number of neighbors (UNN) of the proposed estimator is established. Such result is useful in the study of some data-driven rules. As a direct application and consequence of the conditional density estimation, we derive the UNN consistency of the conditional mode function estimator. Finally, to highlight the efficiency and superiority of the obtained results, we applied our new estimator to real data and compare it to its existing competitive estimator.

APA, Harvard, Vancouver, ISO, and other styles

13

Li, Degui, Zudi Lu, and Oliver Linton. "LOCAL LINEAR FITTING UNDER NEAR EPOCH DEPENDENCE: UNIFORM CONSISTENCY WITH CONVERGENCE RATES." Econometric Theory 28, no. 5 (April 27, 2012): 935–58. http://dx.doi.org/10.1017/s0266466612000011.

Full text

Abstract:

Local linear fitting is a popular nonparametric method in statistical and econometric modeling. Lu and Linton (2007, Econometric Theory23, 37–70) established the pointwise asymptotic distribution for the local linear estimator of a nonparametric regression function under the condition of near epoch dependence. In this paper, we further investigate the uniform consistency of this estimator. The uniform strong and weak consistencies with convergence rates for the local linear fitting are established under mild conditions. Furthermore, general results regarding uniform convergence rates for nonparametric kernel-based estimators are provided. The results of this paper will be of wide potential interest in time series semiparametric modeling.

APA, Harvard, Vancouver, ISO, and other styles

14

Zhu, Hong. "Design and Implementation of Vehicle Self-Navigation System in Urban Intelligent Traffic." Applied Mechanics and Materials 241-244 (December 2012): 2107–10. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.2107.

Full text

Abstract:

Compared with the single sensor measuring, the complementary measuring with the dual sensor can solve some key problems in the vehicle self-navigation system. Two sensors’ data must be fused by the federal state estimator. Based on the Singer model, the system equation of Dead Reckoning sensor is nonlinear and the system equation of Global Positioning System sensor is linear. A two-level estimator is designed and implemented in such a way that two local estimators process the linear and nonlinear systems respectively, and the main estimator fuses the data from two local estimators, so that the optimal global state variables can be estimated. The simulation results show that the two-level estimator of dual sensor can increase the vehicle’s self-navigation precision and can be applied in urban intelligent traffic.

APA, Harvard, Vancouver, ISO, and other styles

15

Ayad, Somia, Ali Laksaci, Saâdia Rahmani, and Rachida Rouane. "LOCAL LINEAR MODELLING OF THE CONDITIONAL DISTRIBUTION FUNCTION FOR FUNCTIONAL ERGODIC DATA." Mathematical Modelling and Analysis 27, no. 3 (August 12, 2022): 360–82. http://dx.doi.org/10.3846/mma.2022.14909.

Full text

Abstract:

The focus of functional data analysis has been mostly on independent functional observations. It is therefore hoped that the present contribution will provide an informative account of a useful approach that merges the ideas of the ergodic theory and the functional data analysis by using the local linear approach. More precisely, we aim, in this paper, to estimate the conditional distribution function (CDF) of a scalar response variable given a random variable taking values in a semimetric space. Under the ergodicity assumption, we study the uniform almost complete convergence (with a rate), as well as the asymptotic normality of the constructed estimator. The relevance of the proposed estimator is verified through a simulation study.

APA, Harvard, Vancouver, ISO, and other styles

16

Zhang, Lili, and Jangsun Baek. "The local influence of LIU type estimator in linear mixed model." Journal of the Korean Data and Information Science Society 26, no. 2 (March 31, 2015): 465–74. http://dx.doi.org/10.7465/jkdi.2015.26.2.465.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Puspitawati, A., and N. Chamidah. "Choroidal Neovascularisation Classification on Fundus Retinal Images Using Local Linear Estimator." IOP Conference Series: Materials Science and Engineering 546 (June 26, 2019): 052056. http://dx.doi.org/10.1088/1757-899x/546/5/052056.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Nguyen, Danh V., and Damla Şentürk. "A consistent local linear estimator of the covariate adjusted correlation coefficient." Statistics & Probability Letters 79, no. 15 (August 2009): 1684–89. http://dx.doi.org/10.1016/j.spl.2009.04.021.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Zhao, Wen-Xiao, Wei Xing Zheng, and Er-Wei Bai. "A Recursive Local Linear Estimator for Identification of Nonlinear ARX Systems*." IFAC Proceedings Volumes 45, no. 16 (July 2012): 1517–22. http://dx.doi.org/10.3182/20120711-3-be-2027.00211.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Liu, Bing, Zhen Chen, Xiangdong Liu, and Fan Yang. "An Efficient Nonlinear Filter for Spacecraft Attitude Estimation." International Journal of Aerospace Engineering 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/540235.

Full text

Abstract:

Increasing the computational efficiency of attitude estimation is a critical problem related to modern spacecraft, especially for those with limited computing resources. In this paper, a computationally efficient nonlinear attitude estimation strategy based on the vector observations is proposed. The Rodrigues parameter is chosen as the local error attitude parameter, to maintain the normalization constraint for the quaternion in the global estimator. The proposed attitude estimator is performed in four stages. First, the local attitude estimation error system is described by a polytopic linear model. Then the local error attitude estimator is designed with constant coefficients based on the robustH2filtering algorithm. Subsequently, the attitude predictions and the local error attitude estimations are calculated by a gyro based model and the local error attitude estimator. Finally, the attitude estimations are updated by the predicted attitude with the local error attitude estimations. Since the local error attitude estimator is with constant coefficients, it does not need to calculate the matrix inversion for the filter gain matrix or update the Jacobian matrixes online to obtain the local error attitude estimations. As a result, the computational complexity of the proposed attitude estimator reduces significantly. Simulation results demonstrate the efficiency of the proposed attitude estimation strategy.

APA, Harvard, Vancouver, ISO, and other styles

21

Sriliana, Idhia, I. Nyoman Budiantara, and Vita Ratnasari. "A Truncated Spline and Local Linear Mixed Estimator in Nonparametric Regression for Longitudinal Data and Its Application." Symmetry 14, no. 12 (December 19, 2022): 2687. http://dx.doi.org/10.3390/sym14122687.

Full text

Abstract:

Longitudinal data modeling is widely carried out using parametric methods. However, when the parametric model is misspecified, the obtained estimator might be severely biased and lead to erroneous conclusions. In this study, we propose a new estimation method for longitudinal data modeling using a mixed estimator in nonparametric regression. The objective of this study was to estimate the nonparametric regression curve for longitudinal data using two combined estimators: truncated spline and local linear. The weighted least square method with a two-stage estimation procedure was used to obtain the regression curve estimation of the proposed model. To account for within-subject correlations in the longitudinal data, a symmetric weight matrix was given in the regression curve estimation. The best model was determined by minimizing the generalized cross-validation value. Furthermore, an application to a longitudinal dataset of the poverty gap index in Bengkulu Province, Indonesia, was conducted to illustrate the performance of the proposed mixed estimator. Compared to the single estimator, the truncated spline and local linear mixed estimator had better performance in longitudinal data modeling based on the GCV value. Additionally, the empirical results of the best model indicated that the proposed model could explain the data variation exceptionally well.

APA, Harvard, Vancouver, ISO, and other styles

22

Xu, Ke-Li. "REWEIGHTED FUNCTIONAL ESTIMATION OF DIFFUSION MODELS." Econometric Theory 26, no. 2 (September 30, 2009): 541–63. http://dx.doi.org/10.1017/s0266466609100087.

Full text

Abstract:

The local linear method is popular in estimating nonparametric continuous-time diffusion models, but it may produce negative results for the diffusion (or volatility) functions and thus lead to insensible inference. We demonstrate this using U.S. interest rate data. We propose a new functional estimation method of the diffusion coefficient based on reweighting the conventional Nadaraya–Watson estimator. It preserves the appealing bias properties of the local linear estimator and is guaranteed to be nonnegative in finite samples. A limit theory is developed under mild requirements (recurrence) of the data generating mechanism without assuming stationarity or ergodicity.

APA, Harvard, Vancouver, ISO, and other styles

23

Wang, Qiying, and Peter C. B. Phillips. "ASYMPTOTIC THEORY FOR ZERO ENERGY FUNCTIONALS WITH NONPARAMETRIC REGRESSION APPLICATIONS." Econometric Theory 27, no. 2 (August 27, 2010): 235–59. http://dx.doi.org/10.1017/s0266466610000277.

Full text

Abstract:

A local limit theorem is given for the sample mean of a zero energy function of a nonstationary time series involving twin numerical sequences that pass to infinity. The result is applicable in certain nonparametric kernel density estimation and regression problems where the relevant quantities are functions of both sample size and bandwidth. An interesting outcome of the theory in nonparametric regression is that the linear term is eliminated from the asymptotic bias. In consequence and in contrast to the stationary case, the Nadaraya–Watson estimator has the same limit distribution (to the second order including bias) as the local linear nonparametric estimator.

APA, Harvard, Vancouver, ISO, and other styles

24

Duan, X. L., Z. M. Qian, and W. A. Zheng. "On Local Linear Approximations to Diffusion Processes." International Journal of Mathematics and Mathematical Sciences 2011 (2011): 1–26. http://dx.doi.org/10.1155/2011/906846.

Full text

Abstract:

Diffusion models have been used extensively in many applications. These models, such as those used in the financial engineering, usually contain unknown parameters which we wish to determine. One way is to use the maximum likelihood method with discrete samplings to devise statistics for unknown parameters. In general, the maximum likelihood functions for diffusion models are not available, hence it is difficult to derive the exact maximum likelihood estimator (MLE). There are many different approaches proposed by various authors over the past years, see, for example, the excellent books and Kutoyants (2004), Liptser and Shiryayev (1977), Kushner and Dupuis (2002), and Prakasa Rao (1999), and also the recent works by Aït-Sahalia (1999), (2004), (2002), and so forth. Shoji and Ozaki (1998; see also Shoji and Ozaki (1995) and Shoji and Ozaki (1997)) proposed a simple local linear approximation. In this paper, among other things, we show that Shoji's local linear Gaussian approximation indeed yields a good MLE.

APA, Harvard, Vancouver, ISO, and other styles

25

Żychaluk, K. "Bootstrap bandwidth selection method for local linear estimator in exponential family models." Journal of Nonparametric Statistics 26, no. 2 (March 10, 2014): 305–19. http://dx.doi.org/10.1080/10485252.2014.885023.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Bâ, Diam, Cheikh Tidiane Seck, and Gane Samb Lô. "Asymptotic Confidence Bands for Copulas Based on the Local Linear Kernel Estimator." Applied Mathematics 06, no. 12 (2015): 2077–95. http://dx.doi.org/10.4236/am.2015.612183.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Benkhaled, Abdelkader, and Fethi Madani. "Local linear approach: Conditional density estimate for functional and censored data." Demonstratio Mathematica 55, no. 1 (January 1, 2022): 315–27. http://dx.doi.org/10.1515/dema-2022-0018.

Full text

Abstract:

Abstract Let Y Y be a random real response, which is subject to right censoring by another random variable C C . In this paper, we study the nonparametric local linear estimation of the conditional density of a scalar response variable and when the covariable takes values in a semi-metric space. Our main aim is to prove under some regularity conditions both the pointwise and the uniform almost-sure consistencies with convergence rates of the conditional density estimator related by this estimation procedure.

APA, Harvard, Vancouver, ISO, and other styles

28

Hiabu, Munir, María Dolores Martínez-Miranda, Jens Perch Nielsen, Jaap Spreeuw, Carsten Tanggaard, and Andrés M. Villegas. "Global Polynomial Kernel Hazard Estimation." Revista Colombiana de Estadística 38, no. 2 (July 15, 2015): 399–411. http://dx.doi.org/10.15446/rce.v38n2.51668.

Full text

Abstract:

<p>This paper introduces a new bias reducing method for kernel hazard estimation. The method is called global polynomial adjustment (GPA). It is a global correction which is applicable to any kernel hazard estimator. The estimator works well from a theoretical point of view as it asymptotically reduces bias with unchanged variance. A simulation study investigates the finite-sample properties of GPA. The method is tested on local constant and local linear estimators. From the simulation experiment we conclude that the global estimator improves the goodness-of-fit. An especially encouraging result is that the bias-correction works well for small samples, where traditional bias reduction methods have a tendency to fail.</p>

APA, Harvard, Vancouver, ISO, and other styles

29

Luo, Shuanghua, Cheng-Yi Zhang, and Fengmin Xu. "The Local LinearM-Estimation with Missing Response Data." Journal of Applied Mathematics 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/398082.

Full text

Abstract:

This paper studies the nonparametric regressive function with missing response data. Three local linearM-estimators with the robustness of local linear regression smoothers are presented such that they have the same asymptotic normality and consistency. Then finite-sample performance is examined via simulation studies. Simulations demonstrate that the complete-case dataM-estimator is not superior to the other two local linearM-estimators.

APA, Harvard, Vancouver, ISO, and other styles

30

Poměnková, Jitka. "Nonparametric estimate remarks." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 54, no. 3 (2006): 93–100. http://dx.doi.org/10.11118/actaun200654030093.

Full text

Abstract:

Kernel smoothers belong to the most popular nonparametric functional estimates. They provide a simple way of finding structure in data. The idea of the kernel smoothing can be applied to a simple fixed design regression model. This article is focused on kernel smoothing for fixed design regresion model with three types of estimators, the Gasser-Müller estimator, the Nadaraya-Watson estimator and the local linear estimator. At the end of this article figures for ilustration of desribed estimators on simulated and real data sets are shown.

APA, Harvard, Vancouver, ISO, and other styles

31

Dörsek, Philipp, and Jens M. Melenk. "Symmetry-Free, p-Robust Equilibrated Error Indication for the hp-Version of the FEM in Nearly Incompressible Linear Elasticity." Computational Methods in Applied Mathematics 13, no. 3 (July 1, 2013): 291–304. http://dx.doi.org/10.1515/cmam-2013-0007.

Full text

Abstract:

Abstract. We consider the extension of the p-robust equilibrated error estimator due to Braess, Pillwein and Schöberl to linear elasticity. We derive a formulation where the local mixed auxiliary problems do not require symmetry of the stresses. The resulting error estimator is p-robust, and the reliability estimate is also robust in the incompressible limit if quadratics are included in the approximation space. Extensions to other systems of linear second-order partial differential equations are discussed. Numerical simulations show only moderate deterioration of the effectivity index for a Poisson ratio close to .

APA, Harvard, Vancouver, ISO, and other styles

32

Peng, Liang, and Shan Sun. "Comparisons Between Local Linear Estimator and Kernel Smooth Estimator for a Smooth Distribution Based on MSE Under Right Censoring." Communications in Statistics - Theory and Methods 36, no. 2 (February 6, 2007): 297–312. http://dx.doi.org/10.1080/03610920600974351.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Lin, ZhengYan, YuPing Song, and JiangSheng Yi. "Local linear estimator for stochastic differential equations driven by α-stable Lévy motions." Science China Mathematics 57, no. 3 (December 30, 2013): 609–26. http://dx.doi.org/10.1007/s11425-013-4628-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Khardani, Salah, and Abdelkader Benkhaled. "A nonparametric estimation of the conditional ageing intensity function in censored data: A local linear approach." Mathematica Slovaca 71, no. 2 (April 1, 2021): 429–38. http://dx.doi.org/10.1515/ms-2017-0479.

Full text

Abstract:

Abstract In this paper, we investigate the problem of the local linear estimation of the conditional ageing intensity function, when the variable of interest is subject to random right-censored. We establish under appropriate conditions the asymptotic normality of this estimator.

APA, Harvard, Vancouver, ISO, and other styles

35

Zhou, Xiaoshuang, Xiulian Gao, Yukun Zhang, Xiuling Yin, and Yanfeng Shen. "Efficient Estimation for the Derivative of Nonparametric Function by Optimally Combining Quantile Information." Symmetry 13, no. 12 (December 10, 2021): 2387. http://dx.doi.org/10.3390/sym13122387.

Full text

Abstract:

In this article, we focus on the efficient estimators of the derivative of the nonparametric function in the nonparametric quantile regression model. We develop two ways of combining quantile regression information to derive the estimators. One is the weighted composite quantile regression estimator based on the quantile weighted loss function; the other is the weighted quantile average estimator based on the weighted average of quantile regression estimators at a single quantile. Furthermore, by minimizing the asymptotic variance, the optimal weight vector is computed, and consequently, the optimal estimator is obtained. Furthermore, we conduct some simulations to evaluate the performance of our proposed estimators under different symmetric error distributions. Simulation studies further illustrate that both estimators work better than the local linear least square estimator for all the symmetric errors considered except the normal error, and the weighted quantile average estimator performs better than the weighted composite quantile regression estimator in most situations.

APA, Harvard, Vancouver, ISO, and other styles

36

Boroumand, Farzaneh, Mohammad Taghi Shakeri, Touka Banaee, Hamidreza Pourreza, and Hassan Doosti. "An Analysis of the Areas Occupied by Vessels in the Ocular Surface of Diabetic Patients: An Application of a Nonparametric Tilted Additive Model." International Journal of Environmental Research and Public Health 18, no. 7 (April 2, 2021): 3735. http://dx.doi.org/10.3390/ijerph18073735.

Full text

Abstract:

(1) Background: As diabetes melllitus (DM) can affect the microvasculature, this study evaluates different clinical parameters and the vascular density of ocular surface microvasculature in diabetic patients. (2) Methods: In this cross-sectional study, red-free conjunctival photographs of diabetic individuals aged 30–60 were taken under defined conditions and analyzed using a Radon transform-based algorithm for vascular segmentation. The Areas Occupied by Vessels (AOV) images of different diameters were calculated. To establish the sum of AOV of different sized vessels. We adopt a novel approach to investigate the association between clinical characteristics as the predictors and AOV as the outcome, that is Tilted Additive Model (TAM). We use a tilted nonparametric regression estimator to estimate the nonlinear effect of predictors on the outcome in the additive setting for the first time. (3) Results: The results show Age (p-value = 0.019) and Mean Arterial Pressure (MAP) have a significant linear effect on AOV (p-value = 0.034). We also find a nonlinear association between Body Mass Index (BMI), daily Urinary Protein Excretion (UPE), Hemoglobin A1C, and Blood Urea Nitrogen (BUN) with AOV. (4) Conclusions: As many predictors do not have a linear relationship with the outcome, we conclude that the TAM will help better elucidate the effect of the different predictors. The highest level of AOV can be seen at Hemoglobin A1C of 9% and AOV increases when the daily UPE exceeds 600 mg. These effects need to be considered in future studies of ocular surface vessels of diabetic patients.

APA, Harvard, Vancouver, ISO, and other styles

37

Chamidah, N., E. Tjahjono, A. R. Fadilah, and B. Lestari. "Standard Growth Charts for Weight of Children in East Java Using Local Linear Estimator." Journal of Physics: Conference Series 1097 (September 2018): 012092. http://dx.doi.org/10.1088/1742-6596/1097/1/012092.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Chamidah, Nur, Yolanda Swastika Yonani, Elly Ana, and Budi Lestari. "Identification the number of Mycobacterium tuberculosis based on sputum image using local linear estimator." Bulletin of Electrical Engineering and Informatics 9, no. 5 (October 1, 2020): 2109–16. http://dx.doi.org/10.11591/eei.v9i5.2021.

Full text

Abstract:

Infectious disease caused by infection of Mycobacterium tuberculosis is called tuberculosis (TB). A common method in detecting TB is by identifying number of mycobacterium TB in sputum manually. Unfortunately, manually calculation by pathologists take a relatively long time. Previous researches on TB bacteria were still limited to detect the absence or presence of mycobacterium TB in images of sputum. This research aims are identifying number of mycobacterium TB and determining accuracy of classification TB severity by approaching nonparametric Poisson regression model and applying an estimator namely local linear. Steps include processing of image, reducing of dimension by applying partial least square and discrete wavelet transformation, and then identifying the number of mycobacterium TB by using the proposed model approach. In this research, we get deviance values of 28.410 for nonparametric and 93.029 for parametric approaches and the average of classification accuracy values for 4 iterations of 92.75% for nonparametric and 85.5% for parametric approaches. Thus, for identifying many of mycobacterium TB met in images of sputum and classifying of TB severity, the proposed identifying method gives higher accuracy and shorter time in identifying number of mycobacterium TB than parametric linear regression method.

APA, Harvard, Vancouver, ISO, and other styles

39

Benkhaled, Abdelkader, Fethi Madani, and Salah Khardani. "Strong consistency of local linear estimation of a conditional density function under random censorship." Arabian Journal of Mathematics 9, no. 3 (May 16, 2020): 513–29. http://dx.doi.org/10.1007/s40065-020-00282-1.

Full text

Abstract:

Abstract In this paper, we study nonparametric local linear estimation of the conditional density of a randomly censored scalar response variable given a functional random covariate. We establish under general conditions the pointwise almost sure convergence with rates of this estimator under $$\alpha $$ α -mixing dependence. Finally, to show interests of our results, on the practical point of view, we have conducted a computational study, first on a simulated data and, then on some real data concerning Kidney transplant data.

APA, Harvard, Vancouver, ISO, and other styles

40

Luo, Shuanghua, Cheng-yi Zhang, and Meihua Wang. "Composite Quantile Regression for Varying Coefficient Models with Response Data Missing at Random." Symmetry 11, no. 9 (August 21, 2019): 1065. http://dx.doi.org/10.3390/sym11091065.

Full text

Abstract:

Composite quantile regression (CQR) estimation and inference are studied for varying coefficient models with response data missing at random. Three estimators including the weighted local linear CQR (WLLCQR) estimator, the nonparametric WLLCQR (NWLLCQR) estimator, and the imputed WLLCQR (IWLLCQR) estimator are proposed for unknown coefficient functions. Under some mild conditions, the proposed estimators are asymptotic normal. Simulation studies demonstrate that the unknown coefficient estimators with IWLLCQR are superior to the other two with WLLCQR and NWLLCQR. Moreover, bootstrap test procedures based on the IWLLCQR fittings is developed to test whether the coefficient functions are actually varying. Finally, a type of investigated real-life data is analyzed to illustrated the applications of the proposed method.

APA, Harvard, Vancouver, ISO, and other styles

41

Zhang, Peng, Wen Juan Qi, and Zi Li Deng. "Covariance Intersection Fusion Kalman Estimator for Multi-Sensor System with Measurements Delays." Applied Mechanics and Materials 475-476 (December 2013): 460–65. http://dx.doi.org/10.4028/www.scientific.net/amm.475-476.460.

Full text

Abstract:

To handle the state estimation fusion problem between local estimation errors for the system with unknown cross-covariances and to avoid a large computation complexity of cross-covariances, for a multi-sensor linear discrete time-invariant stochastic system with time-delayed measurements, by the measurement transformation method, an equivalent system without measurement delays is obtained, and then using the covariance intersection (CI) fusion method, the covariance intersection fusion steady-state Kalman estimator is presented. It is proved that its accuracy is higher than that of each local estimator, and is lower than that of optimal Kalman fuser weighted by matrices with known cross-covariances. A Monte-Carlo simulation example shows the above accuracy relations, hence it has good performances.

APA, Harvard, Vancouver, ISO, and other styles

42

Carstensen, Carsten, and Martin Eigel. "Reliable Averaging for the Primal Variable in the Courant FEM and Hierarchical Error Estimators on Red-Refined Meshes." Computational Methods in Applied Mathematics 16, no. 2 (April 1, 2016): 213–30. http://dx.doi.org/10.1515/cmam-2016-0010.

Full text

Abstract:

AbstractA hierarchical a posteriori error estimator for the first-order finite element method (FEM) on a red-refined triangular mesh is presented for the 2D Poisson model problem. Reliability and efficiency with some explicit constant is proved for triangulations with inner angles smaller than or equal to ${\frac{\pi }{2}}$. The error estimator does not rely on any saturation assumption and is valid even in the pre-asymptotic regime on arbitrarily coarse meshes. The evaluation of the estimator is a simple post-processing of the piecewise linear FEM without any extra solve plus a higher-order approximation term. The results also allow the striking observation that arbitrary local averaging of the primal variable leads to a reliable and efficient error estimation. Several numerical experiments illustrate the performance of the proposed a posteriori error estimator for computational benchmarks.

APA, Harvard, Vancouver, ISO, and other styles

43

Zhang, Peng, Shuyu Zhou, Peng Liu, and Mengwei Li. "Distributed Ellipsoidal Intersection Fusion Estimation for Multi-Sensor Complex Systems." Sensors 22, no. 11 (June 6, 2022): 4306. http://dx.doi.org/10.3390/s22114306.

Full text

Abstract:

This paper investigates the problem of distributed ellipsoidal intersection (DEI) fusion estimation for linear time-varying multi-sensor complex systems with unknown input disturbances and measurement data transmission delays. For the problem with external unknown input disturbance signals, a non-informative prior distribution is used to model the problem. A set of independent random variables obeying Bernoulli distribution is also used to describe the situation of measurement data transmission delay caused by network channel congestion, and appropriate buffer areas are added at the link nodes to retrieve the delayed transmission data values. For multi-sensor systems with complex situations, a minimum mean square error (MMSE) local estimator is designed in a Bayesian framework based on the maximum a posteriori (MAP) estimation criterion. In order to deal with the unknown correlations among the local estimators and to select the fusion estimator with lower computational complexity, the fusion estimator is designed using ellipsoidal intersection (EI) fusion technique, and the consistency of the estimator is demonstrated. In this paper, the difference between DEI fusion and distributed covariance intersection (DCI) fusion and centralized fusion estimation is analyzed by a numerical example, and the superiority of the DEI fusion method is demonstrated.

APA, Harvard, Vancouver, ISO, and other styles

44

ZHANG, Z. H., Z. J. YANG, and GUOHUA LIU. "AN ADAPTIVE TIME-STEPPING PROCEDURE BASED ON THE SCALED BOUNDARY FINITE ELEMENT METHOD FOR ELASTODYNAMICS." International Journal of Computational Methods 09, no. 01 (March 2012): 1240007. http://dx.doi.org/10.1142/s0219876212400075.

Full text

Abstract:

This study develops an adaptive time-stepping procedure of Newmark integration scheme for transient elastodynamic problems, based on the semi-analytical scaled boundary finite element method (SBFEM). In each time step, a posteriori local error estimator based on the linear distributed acceleration is employed to estimate the error caused by the time discretization. The total energy of the domain, consisting of the kinetic energy and the strain energy, is calculated semi-analytically. The time increment is automatically adjusted according to a simple criterion. Three examples with stress wave propagation were modeled. The numerical results show that the developed method is capable of limiting the local error estimator within specified targets by using an optimal time increment in each time step.

APA, Harvard, Vancouver, ISO, and other styles

45

Cui, Shitong, Le Liu, Wei Xing, and Xudong Zhao. "Periodic Event-Triggered Estimation for Networked Control Systems." Electronics 10, no. 18 (September 10, 2021): 2215. http://dx.doi.org/10.3390/electronics10182215.

Full text

Abstract:

This paper considers the problem of remote state estimation in a linear discrete invariant system, where a smart sensor is utilized to measure the system state and generate a local estimate. The communication depends on an event scheduler in the smart sensor. When the channel between the remote estimator and the smart sensor is activated, the remote estimator simply adopts the estimate transmitted by the smart sensor. Otherwise, it calculates an estimate based on the available information. The closed-form of the minimum mean-square error (MMSE) estimator is introduced, and we use Gaussian preserving event-based sensor scheduling to obtain an ideal compromise between the communication cost and estimation quality. Furthermore, we calculate a variation range of communication probability, which helps to design the policy of event-triggered estimation. Finally, the simulation results are given to illustrate the effectiveness of the proposed event-triggered estimator.

APA, Harvard, Vancouver, ISO, and other styles

46

James, Richard P., Paul M. Markowski, and J. Michael Fritsch. "Bow Echo Sensitivity to Ambient Moisture and Cold Pool Strength." Monthly Weather Review 134, no. 3 (March 1, 2006): 950–64. http://dx.doi.org/10.1175/mwr3109.1.

Full text

Abstract:

Abstract Bow echo development within quasi-linear convective systems is investigated using a storm-scale numerical model. A strong sensitivity to the ambient water vapor mixing ratio is demonstrated. Relatively dry conditions at low and midlevels favor intense cold-air production and strong cold pool development, leading to upshear-tilted, “slab-like” convection for various magnitudes of convective available potential energy (CAPE) and low-level shear. High relative humidity in the environment tends to reduce the rate of production of cold air, leading to weak cold pools and downshear-tilted convective systems, with primarily cell-scale three-dimensionality in the convective region. At intermediate moisture contents, long-lived, coherent bowing segments are generated within the convective line. In general, the scale of the coherent three-dimensional structures increases with increasing cold pool strength. The bowing lines are characterized in their developing and mature stages by segments of the convective line measuring 15–40 km in length over which the cold pool is much stronger than at other locations along the line. The growth of bow echo structures within a linear convective system appears to depend critically on the local strengthening of the cold pool to the extent that the convection becomes locally upshear tilted. A positive feedback process is thereby initiated, allowing the intensification of the bow echo. If the environment favors an excessively strong cold pool, however, the entire line becomes uniformly upshear tilted relatively quickly, and the along-line heterogeneity of the bowing line is lost.

APA, Harvard, Vancouver, ISO, and other styles

47

Zhao, Wenxiao, Wei Xing Zheng, and Er-Wei Bai. "A Recursive Local Linear Estimator for Identification of Nonlinear ARX Systems: Asymptotical Convergence and Applications." IEEE Transactions on Automatic Control 58, no. 12 (December 2013): 3054–69. http://dx.doi.org/10.1109/tac.2013.2273283.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Ahmad, Wasim, Sheraz Ali Khan, and Jong-Myon Kim. "Estimating the remaining useful life of bearings using a neuro-local linear estimator-based method." Journal of the Acoustical Society of America 141, no. 5 (May 2017): EL452—EL457. http://dx.doi.org/10.1121/1.4983341.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Ferrigno, Sandie, Myriam Maumy-Bertrand, and Aurélie Muller. "Uniform law of the logarithm for the local linear estimator of the conditional distribution function." Comptes Rendus Mathematique 348, no. 17-18 (September 2010): 1015–19. http://dx.doi.org/10.1016/j.crma.2010.08.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Wang, Xin, Zhi Yu, Le Yang, and Ji Li. "Design and Analysis of a Non-Iterative Estimator for Target Location in Multistatic Sonar Systems with Sensor Position Uncertainties." Mathematics 8, no. 1 (January 15, 2020): 129. http://dx.doi.org/10.3390/math8010129.

Full text

Abstract:

Target location is the basic application of a multistatic sonar system. Determining the position/velocity vector of a target from the related sonar observations is a nonlinear estimation problem. The presence of possible sensor position uncertainties turns this problem into a more challenging hybrid parameter estimation problem. Conventional gradient-based iterative estimators suffer from the problems of initialization difficulties and local convergence. Even if there is no problem with initialization and convergence, a large computational cost is required in most cases. In view of these drawbacks, we develop a computationally efficient non-iterative position/velocity estimator. The main numerical computation involved is the weighted least squares optimization, which makes the estimator computationally efficient. Parameter transformation, model linearization and two-stage processing are exploited to prevent the estimator from iterative computation. Through performance analysis and experimental verification, we find that the proposed estimator reaches the hybrid Cramér–Rao bound and has linear computational complexity.

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!