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Published on: July 3, 2020
Graphical evaluation of the ridge-type robust regression estimators in mixture experiments
Ali Erkoc1, Esra Emiroglu2, Kadri Ulas Akay2
1Department of Statistics, Faculty of Science and Letters, Mimar Sinan Fine Arts University, Sisli, 34380 Istanbul, Turkey.
Ordinary least squares (OLS) struggles with multicollinearity and outliers in mixture experiments. This study evaluates ridge-type robust estimators to improve parameter estimation, offering a graphical method for selecting the best estimator.
Area of Science:
- Statistics
- Experimental Design
- Chemometrics
Background:
- Ordinary least squares (OLS) is standard for parameter estimation in mixture experiments.
- OLS performance degrades significantly with multicollinearity and outliers.
- Combined multicollinearity and outliers pose a substantial challenge in mixture analysis.
Purpose of the Study:
- To evaluate ridge-type robust estimators for mixture experiments.
- To address parameter estimation issues caused by multicollinearity and outliers.
- To introduce a graphical method for selecting optimal ridge-type robust estimators.
Main Methods:
- Investigated various ridge-type robust regression estimators.
- Employed fraction of design space plots for biasing parameter selection.
- Assessed estimator performance based on scaled mean squared error of prediction.
Main Results:
- Ridge-type robust estimators demonstrate potential in mitigating OLS limitations.
- The fraction of design space plots effectively guide the selection of biasing parameters.
- The proposed graphical approach provides a practical tool for analyzing mixture data.
Conclusions:
- Ridge-type robust estimators offer a viable alternative to OLS in challenging mixture experiments.
- The graphical selection method enhances the reliability of parameter estimation.
- The study provides a practical framework for robust analysis of mixture data with outliers and multicollinearity.
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