Noncommutative martingale concentration inequalities
arXiv:1409.0342 · doi:10.1215/ijm/1436275498
Abstract
We establish an Azuma type inequality under a Lipshitz condition for martingales in the framework of noncommutative probability spaces and apply it to deduce a noncommutative Heoffding inequality as well as a noncommutative McDiarmid type inequality. We also provide a noncommutative Azuma inequality for noncommutative supermartingales in which instead of a fixed upper bound for the variance we assume that the variance is bounded above by a linear function of variables. We then employ it to deduce a noncommutative Bernstein inequality and an inequality involving -norm of the sum of a martingale difference.
18 pages, to appear in Illinois J. Math