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arXiv · 1508.07564

Weak Tail Conditions for Local Martingales

Hardy Hulley·Johannes Ruf
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Abstract

The following conditions are necessary and sufficient for an arbitrary càdlàg local martingale to be a uniformly integrable martingale: (i) The weak tail of the supremum of its modulus is zero; (ii) its jumps at the first-exit times from compact intervals converge to zero in $L^1$, on the events that those times are finite; and (iii) its almost sure limit is an integrable random variable.

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Hardy Hulley, Johannes Ruf. 2015-08-30. Weak Tail Conditions for Local Martingales. https://arxiv.org/abs/1508.07564

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