| Authors: | Jeff T. Terpstra, Joseph W. McKean |
| Title: | [download] (4749)Rank-Based Analysis of Linear Models Using R |
| Reference: | Vol. 14, Issue 7, Jul 2005 Submitted 2004-04-06, Accepted 2005-07-01 |
| Type: | Article |
| Abstract: | It is well-known that Wilcoxon procedures out perform least squares procedures when the data deviate from normality and/or contain outliers. These procedures can be generalized by introducing weights; yielding so-called weighted Wilcoxon (WW) techniques. In this paper we demonstrate how WW-estimates can be calculated using an L1 regression routine. More importantly, we present a collection of functions that can be used to implement a robust analysis of a linear model based on WW-estimates. For instance, estimation, tests of linear hypotheses, residual analyses, and diagnostics to detect differences in fits for various weighting schemes are discussed. We analyze a regression model, designed experiment, and autoregressive time series model for the sake of illustration. We have chosen to implement the suite of functions using the R statistical software package. Because R is freely available and runs on multiple platforms, WW-estimation and associated inference is now universally accessible. |
| Paper: | [download] (4749)Rank-Based Analysis of Linear Models Using R (application/pdf, 675.4 KB) |
| Supplements: | [download] (624)wwcode.zip: wwcode (application/x-zip-compressed, 43.4 KB) |
| [download] (583)wwcode.zip: wwcode (Updated 1/14/07) (application/x-zip-compressed, 44.7 KB) |
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| Resources: | BibTeX | OAI |
