hide
Free keywords:
-
Abstract:
We present the first (to our knowledge) approximation algo-
rithm for tensor clusteringa powerful generalization to basic 1D clustering. Tensors are increasingly common in modern applications dealing
with complex heterogeneous data and clustering them is a fundamental
tool for data analysis and pattern discovery. Akin to their 1D cousins,
common tensor clustering formulations are NP-hard to optimize. But,
unlike the 1D case no approximation algorithms seem to be known. We
address this imbalance and build on recent co-clustering work to derive
a tensor clustering algorithm with approximation guarantees, allowing
metrics and divergences (e.g., Bregman) as objective functions. Therewith, we answer two open questions by Anagnostopoulos et al. (2008).
Our analysis yields a constant approximation factor independent of data
size; a worst-case example shows this factor to be tight for Euclidean
co-clustering. However, empirically the approximation factor is observed
to be conservative, so our method can also be used in practice.