# Walks on SPR Neighborhoods

@article{Caceres2011WalksOS, title={Walks on SPR Neighborhoods}, author={Alan Joseph J. Caceres and Juan Castillo and Jinnie Lee and Katherine St. John}, journal={IEEE/ACM Transactions on Computational Biology and Bioinformatics}, year={2011}, volume={10}, pages={236-239} }

A nearest-neighbor-interchange (NNI)-walk is a sequence of unrooted phylogenetic trees, T1,T2, ... ,Tk where each consecutive pair of trees differs by a single NNI move. We give tight bounds on the length of the shortest NNI-walks that visit all trees in a subtree-prune-and-regraft (SPR) neighborhood of a given tree. For any unrooted, binary tree, T, on n leaves, the shortest walk takes ⊖(n2) additional steps more than the number of trees in the SPR neighborhood. This answers Bryant's Second…

## 2 Citations

### Characterizing Local Optima for Maximum Parsimony

- Computer ScienceBulletin of Mathematical Biology
- 2016

It is shown that when neighbors are defined via the subtree prune and regraft metric, there is a single local optimum for perfect sequence data, and thus, every such search finds a global optimum quickly.

### Characterizing Local Optima for Maximum Parsimony

- Computer ScienceBulletin of mathematical biology
- 2016

It is shown that when neighbors are defined via the subtree prune and regraft metric, there is a single local optimum for perfect sequence data, and thus, every such search finds a global optimum quickly.

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