Let $ W = X_1+X_2+\cdots + X_N $ be a random sum and $ Z $ be the standard normal random variable. In this paper, we investigated uniform and non-uniform bounds of the stop-loss distance, which measures the difference between two random variables, $ W $ and $ Z $, using the expression $ |Eh_k(W) - Eh_k(Z)| $, where $ h_k(x) = (x-k)^+ $ is a call function. In particular, we focused on the case that $ X_1, X_2, \ldots $ are independent random variables, and $ N $ is a non-negative, integer-valued random variable independent of the $ X_j $'s. Our methods were Stein's method and the concentration inequality approach. The value $ Eh_k(W) = E(W-k)^+ $ represents the excess over a threshold and is relevant to applications in collateralized debt obligations (CDOs) and the collective risk model.
Citation: Punyapat Kammoo, Kritsana Neammanee, Kittipong Laipaporn. Bounds for the stop-loss distance of an independent random sum via Stein's method[J]. AIMS Mathematics, 2025, 10(6): 13082-13103. doi: 10.3934/math.2025587
Let $ W = X_1+X_2+\cdots + X_N $ be a random sum and $ Z $ be the standard normal random variable. In this paper, we investigated uniform and non-uniform bounds of the stop-loss distance, which measures the difference between two random variables, $ W $ and $ Z $, using the expression $ |Eh_k(W) - Eh_k(Z)| $, where $ h_k(x) = (x-k)^+ $ is a call function. In particular, we focused on the case that $ X_1, X_2, \ldots $ are independent random variables, and $ N $ is a non-negative, integer-valued random variable independent of the $ X_j $'s. Our methods were Stein's method and the concentration inequality approach. The value $ Eh_k(W) = E(W-k)^+ $ represents the excess over a threshold and is relevant to applications in collateralized debt obligations (CDOs) and the collective risk model.
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