Abstract
In this article we provide several new approximation methods for the Karcher or Fréchet mean on NPC spaces. We provide a non-stochastic version of Sturm’s law of large numbers, i.e. a weighted deterministic walk for the Karcher mean. Then we extend certain subgradient methods existing in the case of Riemannian manifolds to the case of non-differentiable case of NPC spaces for the Karcher mean. These methods not only provide new intrinsic algorithms for computing the Karcher mean in NPC spaces but also new theoretical results and characterizations for the Karcher mean.
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Pálfia, M. (2013). Deterministic Walks and Quasi-Subgradient Methods for the Karcher Mean on NPC Spaces. In: Nielsen, F., Barbaresco, F. (eds) Geometric Science of Information. GSI 2013. Lecture Notes in Computer Science, vol 8085. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-40020-9_90
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DOI: https://doi.org/10.1007/978-3-642-40020-9_90
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