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A Practical Guide to Phylogenetics for Nonexperts
Published on: February 5, 2014
Penalized likelihood phylogenetic inference: bridging the parsimony-likelihood gap
Junhyong Kim1, Michael J Sanderson
1Department of Biology and Penn Genome Frontiers Institute, University of Pennsylvania, Philadelphia, Pennsylvania, USA. junhyong@sas.upenn.edu
Systematic Biology
|October 15, 2008
Summary
We introduce a penalized likelihood (PL) framework for flexible control of phylogenetic model complexity. This unified approach encompasses various existing estimators, offering a powerful tool for molecular data analysis.
Area of Science:
- Phylogenetics
- Computational Biology
- Statistical Modeling
Background:
- Molecular data for phylogeny estimation is increasingly diverse and complex.
- Existing models and estimators struggle to handle this heterogeneity effectively.
Purpose of the Study:
- To propose a unified penalized likelihood (PL) framework for phylogeny estimation.
- To enable smooth control over the complexity of underlying phylogenetic models.
- To demonstrate the flexibility and broad applicability of the PL framework.
Main Methods:
- Development of a penalized likelihood (PL) framework.
- Demonstration using a four-taxon tree case.
- Investigation of the properties of the PL framework.
Main Results:
- The PL framework provides a unified approach encompassing various existing estimators (e.g., maximum parsimony, homogeneous likelihood, gamma mixture likelihood).
- Penalties allow for partitioning model complexity into controllable classes.
- Flexible control over model complexity is achieved.
Conclusions:
- The proposed PL framework offers a versatile and unified approach to phylogeny estimation.
- It allows for nuanced control over model complexity, accommodating diverse molecular data.
- This framework has the potential to improve the accuracy and robustness of phylogenetic analyses.
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