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Madison, WI 53726-2398
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Title: When Good Confidence Intervals Go Bad: Predictor Sort Experiments and ANOVA

Source: The American Statistician, February 1999, Volume 53, Number 1; pp. 38-42.

Author(s)Verrill, Steve

Publication Year: 1999  View PDF »

Category: Journal Articles

Abstract: A predictor sort experiment is one in which experimental units are allocated on the basis of the values of a predictor variable that is correlated with the response. Standard ANOVA analyses of predictor sort experiments can lead to confidence intervals whose actual coverages are poor matches to nominal coverages. Correct coverages can be obtained by adjusting confidence interval lengths by appropriate factors, or by performing analyses of covariance.

Keywords: Analysis of covariance; Analysis of variance; Blocked analysis of variance: Concomitant variable; Predictor sort sampling.

Publication Review Process: Non-Refereed (Other)

File size: 132 kb(s)

Date posted: 07/10/2013
RITS Product ID: 64431
Current FPL Scientist associated with this product
Verrill, Steve P.
Mathematical Statistician

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