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Journal ArticleDOI

Robust Locally Weighted Regression and Smoothing Scatterplots

William S. Cleveland
- 01 Dec 1979 - 
- Vol. 74, Iss: 368, pp 829-836
TLDR
Robust locally weighted regression as discussed by the authors is a method for smoothing a scatterplot, in which the fitted value at z k is the value of a polynomial fit to the data using weighted least squares, where the weight for (x i, y i ) is large if x i is close to x k and small if it is not.
Abstract
The visual information on a scatterplot can be greatly enhanced, with little additional cost, by computing and plotting smoothed points. Robust locally weighted regression is a method for smoothing a scatterplot, (x i , y i ), i = 1, …, n, in which the fitted value at z k is the value of a polynomial fit to the data using weighted least squares, where the weight for (x i , y i ) is large if x i is close to x k and small if it is not. A robust fitting procedure is used that guards against deviant points distorting the smoothed points. Visual, computational, and statistical issues of robust locally weighted regression are discussed. Several examples, including data on lead intoxication, are used to illustrate the methodology.

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Statistical Comparisons of Classifiers over Multiple Data Sets

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Generalized Additive Models.

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Experimental Design and Data Analysis for Biologists

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Multivariable prognostic models: issues in developing models, evaluating assumptions and adequacy, and measuring and reducing errors

TL;DR: In this article, an easily interpretable index of predictive discrimination as well as methods for assessing calibration of predicted survival probabilities are discussed, which are particularly needed for binary, ordinal, and time-to-event outcomes.
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Lung Cancer, Cardiopulmonary Mortality, and Long-term Exposure to Fine Particulate Air Pollution

TL;DR: Fine particulate and sulfur oxide--related pollution were associated with all-cause, lung cancer, and cardiopulmonary mortality and long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopULmonary and lung cancer mortality.
References
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Book

Applied Regression Analysis

TL;DR: In this article, the Straight Line Case is used to fit a straight line by least squares, and the Durbin-Watson Test is used for checking the straight line fit.
Journal ArticleDOI

Exploratory data analysis

F. N. David, +1 more
- 01 Dec 1977 - 
Journal ArticleDOI

Exploratory Data Analysis.

Journal ArticleDOI

Robust Regression: Asymptotics, Conjectures and Monte Carlo

TL;DR: In this paper, a formal power series expansion of the initial terms of a power-series expansion with respect to the number of observations has been proposed, in most cases down to 4 observations per parameter.
Journal ArticleDOI

Consistent Nonparametric Regression

TL;DR: In this article, a sequence of probability weight functions defined in terms of nearest neighbors is constructed and sufficient conditions for consistency are obtained, which are applied to verify the consistency of the estimators of the various quantities discussed above and the consistency in Bayes risk of the approximate Bayes rules.