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arXiv · 1411.1594

Joint estimation of $K$ related regression models with simple $L_1$-norm penalties

Edouard Ollier·Vivian Viallon
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Abstract

We propose a new approach, along with refinements, based on $L_1$ penalties and aimed at jointly estimating several related regression models. Its main interest is that it can be rewritten as a weighted lasso on a simple transformation of the original data set. In particular, it does not need new dedicated algorithms and is ready to implement under a variety of regression models, {\em e.g.}, using standard R packages. Moreover, asymptotic oracle properties are derived along with preliminary non-asymptotic results, suggesting good theoretical properties. Our approach is further compared with state-of-the-art competitors under various settings on synthetic data: these empirical results confirm that our approach performs at least similarly to its competitors. As a final illustration, an analysis of road safety data is provided.

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Edouard Ollier, Vivian Viallon. 2014-11-06. Joint estimation of $K$ related regression models with simple $L_1$-norm penalties. https://arxiv.org/abs/1411.1594

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