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arXiv · 1303.6914

One example of general unidentifiable tensors

Luca Chiantini·Massimiliano Mella·Giorgio Ottaviani
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Abstract

The identifiability of parameters in a probabilistic model is a crucial notion in statistical inference. We prove that a general tensor of rank 8 in C^3\otimes C^6\otimes C^6 has at least 6 decompositions as sum of simple tensors, so it is not 8-identifiable. This is the highest known example of balanced tensors of dimension 3, which are not k-identifiable, when k is smaller than the generic rank.

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Luca Chiantini, Massimiliano Mella, Giorgio Ottaviani. 2013-03-27. One example of general unidentifiable tensors. https://arxiv.org/abs/1303.6914

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