Approximate Principal Direction Trees
University of Massachusetts Amherst, 140 Governors Drive, Amherst, MA 01002-9264 USA
arXiv:1206.4668v1 [cs.LG] (18 Jun 2012)
@article{2012arXiv1206.4668M,
author={McCartin-Lim}, M. and {McGregor}, A. and {Wang}, R.},
title={"{Approximate Principal Direction Trees}"},
journal={ArXiv e-prints},
archivePrefix={"arXiv"},
eprint={1206.4668},
primaryClass={"cs.LG"},
keywords={Computer Science – Learning, Computer Science – Data Structures and Algorithms, Statistics – Machine Learning},
year={2012},
month={jun},
adsurl={http://adsabs.harvard.edu/abs/2012arXiv1206.4668M},
adsnote={Provided by the SAO/NASA Astrophysics Data System}
}
We introduce a new spatial data structure for high dimensional data called the emph{approximate principal direction tree} (APD tree) that adapts to the intrinsic dimension of the data. Our algorithm ensures vector-quantization accuracy similar to that of computationally-expensive PCA trees with similar time-complexity to that of lower-accuracy RP trees. APD trees use a small number of power-method iterations to find splitting planes for recursively partitioning the data. As such they provide a natural trade-off between the running-time and accuracy achieved by RP and PCA trees. Our theoretical results establish a) strong performance guarantees regardless of the convergence rate of the power-method and b) that $O(log d)$ iterations suffice to establish the guarantee of PCA trees when the intrinsic dimension is $d$. We demonstrate this trade-off and the efficacy of our data structure on both the CPU and GPU.
June 25, 2012 by hgpu