Convergence of series of moments on general exponential inequality (2103.01996v2)

Abstract: For an array $\left{X_{n,j}, \, 1 \leqslant j \leqslant k_{n}, n \geqslant 1 \right}$ of random variables and a sequence ${c_{n} }$ of positive numbers, sufficient conditions are given under which, for all $\varepsilon > 0$, $\sum_{n=1}^{\infty} c_{n} \mathbb{E} \bigg[{\displaystyle \max_{1 \leqslant i \leqslant k_{n}}} \Big\lvert\sum_{j=1}^{i} (X_{n,j} - \mathbb{E} \, X_{n,j} I_{\left{\lvert X_{n,j} \rvert \leqslant \delta \right}}) \Big\rvert - \varepsilon \bigg]{+}^{p} < \infty,$ where $x{+}$ denotes the positive part of $x$ and $p \geqslant 1$, $\delta > 0$. Our statements are announced in a general setting allowing to conclude the previous convergence for well-known dependent structures. As an application, we study complete consistency and consistency in the $r$th mean of cumulative sum type estimators of the change in the mean of dependent observations.