Appell pseudopolynomials and Erlang-type risk models

作者:Lefevre Claude*; Picard Philippe
来源:Stochastics: An International Journal of Probability and Stochastic Processes , 2014, 86(4): 676-695.
DOI:10.1080/17442508.2013.872645

摘要

Appell polynomials are known to play a key role in certain first-crossing problems. The present paper considers a rather general insurance risk model where the claim interarrival times are independent and exponentially distributed with different parameters, the successive claim amounts may be dependent and the premium income is an arbitrary deterministic function. It is shown that the non-ruin (or survival) probability over a finite horizon may be expressed in terms of a remarkable family of functions, named pseudopolynomials, that generalize the classical Appell polynomials. The presence of that underlying algebraic structure is exploited to provide a closed formula, almost explicit, for the non-ruin probability.