Weighted Median Predictive Techniques for Coe cient Estimation in NonGaussian Markov Random Fields
نویسندگان
چکیده
NonGaussian Markov image models are e ective in the preservation of edge detail in Bayesian formulations of restoration and reconstruction problems. Included in these models are coe cients quantifying the statistical links among pixels in local cliques, which are typically assumed to have an inverse dependence on distance among the corresponding neighboring pixels. Estimation of these coe cients is a nontrivial task for NonGaussian models. We present results for coe cient estimation for a model which is particularly e ective for edge preservation and noise suppression, using a predictive technique analogous to estimation of the weights of optimal weighted median lters.
منابع مشابه
Coefficient of determination in nonlinear signal processing
For statistical design of an optimal "lter, it is probabilistically advantageous to employ a large number of observation random variables; however, estimation error increases with the number of variables, so that variables not contributing to the determination of the target variable can have a detrimental e!ect. In linear "ltering, determination involves the correlation coe$cients among the inp...
متن کاملLarge Scale Experiments Data Analysis for Estimation of Hydrodynamic Force Coefficients Part 1: Time Domain Analysis
This paper describes various time-domain methods useful for analyzing the experimental data obtained from a circular cylinder force in terms of both wave and current for estimation of the drag and inertia coefficients applicable to the Morison’s equation. An additional approach, weighted least squares method is also introduced. A set of data obtained from experiments on heavily roughened circul...
متن کاملPrediction of Longitudinal Dispersion Coe cient in Natural Channels Using Soft Computing Techniques
Accurate estimate of longitudinal dispersion coe cient is essential in many hydraulic and environmental problems such as intake designs, modeling ow in esturies and risk assessment of injection of hazardous pollutants into river ows. Recent research works show that in the absence of knowledge about explicit relationships concerning longitudinal dispersion coe cient and its in uencing parameters...
متن کاملStrong and weak error estimates for the solutions of elliptic partial differential equations with random coefficients
We consider the problem of numerically approximating the solution of an elliptic partial di erential equation with random coe cients and homogeneous Dirichlet boundary conditions. We focus on the case of a lognormal coe cient, we have then to deal with the lack of uniform coercivity and uniform boundedness with respect to the randomness. This model is frequently used in hydrogeology. We approxi...
متن کاملRegression , Density and Spectral Density Estimation
We consider posterior inference in wavelet based models for non-parametric regression with unequally spaced data, density estimation and spectral density estimation. The common theme in all three applications is the lack of posterior independence for the wavelet coe cients djk . In contrast, most commonly considered applications of wavelet decompositions in Statistics are based on a setup which...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1995