Eeciency of Feasible Weighted Least Squares Estimators of the Center and Radius of a Spherical Surface
نویسنده
چکیده
A linear model based on the spherical coordinate system is employed for tting a spherical surface to a data set obtained by a coordinate measuring machine (CMM). In practice, measurement data may have unequal accuracy on the diierent coordinate axes, thus a liner model with heteroscedastic variance of random errors is considered. A feasible weighted least squares estimate is proposed and its superority over the ordinary least square estimate is established.
منابع مشابه
Comparison of the Performance of Geographically Weighted Regression and Ordinary Least Squares for modeling of Sea surface temperature in Oman Sea
In Marine discussions, the study of sea surface temperature (SST) and study of its spatial relationships with other ocean parameters are of particular importance, in such a way that the accurate recognition of the SST relationships with other parameters allows the study of many ocean and atmospheric processes. Therefore, in this study, spatial relations modeling of SST with Surface Wind Speed (...
متن کاملEfficient Estimation of the Density and Cumulative Distribution Function of the Generalized Rayleigh Distribution
The uniformly minimum variance unbiased (UMVU), maximum likelihood, percentile (PC), least squares (LS) and weighted least squares (WLS) estimators of the probability density function (pdf) and cumulative distribution function are derived for the generalized Rayleigh distribution. This model can be used quite effectively in modelling strength data and also modeling general lifetime data. It has...
متن کاملLeast squares weighted residual method for finding the elastic stress fields in rectangular plates under uniaxial parabolically distributed edge loads
In this work, the least squares weighted residual method is used to solve the two-dimensional (2D) elasticity problem of a rectangular plate of in-plane dimensions 2a 2b subjected to parabolic edge tensile loads applied at the two edges x = a. The problem is expressed using Beltrami–Michell stress formulation. Airy’s stress function method is applied to the stress compatibility equation, and th...
متن کاملModified Weighted Least Squares Method to Improve Active Distribution System State Estimation
The development of communications and telecommunications infrastructure, followed by the extension of a new generation of smart distribution grids, has brought real-time control of distribution systems to electrical industry professionals’ attention. Also, the increasing use of distributed generation (DG) resources and the need for participation in the system voltage control, which is possible ...
متن کاملFuzzy Robust Regression Analysis with Fuzzy Response Variable and Fuzzy Parameters Based on the Ranking of Fuzzy Sets
Robust regression is an appropriate alternative for ordinal regression when outliers exist in a given data set. If we have fuzzy observations, using ordinal regression methods can't model them; In this case, using fuzzy regression is a good method. When observations are fuzzy and there are outliers in the data sets, using robust fuzzy regression methods are appropriate alternatives....
متن کامل