Models of Noise and Robust Estimation

Abstract

Given n noisy observations gi of the same quantity f, it is common use to give an estimate of f by minimizing the function sum n sub i = 1(gi - f) 2. From a statistical point of view this corresponds to computing the Maximum Likelihood estimate, under the assumption of Gaussian noise. However, it is well known that this choice leads to results that are very sensitive to the presence of outliers in the data. For this reason it has been proposed to minimize functions of the form sum n sub i = 1(gi-f), where V is a function that increases less rapidly than the square. Several choices for V have been proposed and successfully used to obtain 'robust' estimates. In this paper we show that, for a class of functions V, using these robust estimators corresponds to assuming that data are corrupted by Gaussian noise whose variance fluctuates according to some given probability distribution, that uniquely determines the shape of V.... Robust estimation, Noise, Outliers.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1991
Accession Number
ADA259572

Entities

People

  • Federico Girosi

Organizations

  • Massachusetts Institute of Technology

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Abstracts
  • Artificial Intelligence
  • Cognitive Science
  • Delta Functions
  • Estimators
  • Gaussian Noise
  • Information Processing
  • Information Systems
  • Military Research
  • Monotone Functions
  • Noise
  • Observation
  • Probability
  • Probability Distributions
  • Random Variables
  • Standards

Fields of Study

  • Mathematics

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Naval Personnel Management
  • Regression Analysis.