English

Time-consistency of cash-subadditive risk measures

Risk Management 2015-12-14 v1 Probability Mathematical Finance

Abstract

The main goal of this paper is to investigate under which conditions cash-subadditive convex dynamic risk measures are time-consistent. Proceeding as in Detlefsen and Scandolo \cite{detlef-scandolo} and inspired by their result, we give a dual representation of dynamic cash-subadditive convex risk measures (that can also be seen as particular case of the dual quasiconvex representation). The main result of the paper consists in providing, in the cash-subadditive case, a sufficient condition for strong time-consistency (or recursivity) in terms of a generalized cocycle condition. On one hand, our result can be seen as an extension to cash-subadditive convex dynamic risk measures of Theorem 2.5 in Bion-Nadal \cite{bion-nadal-FS}; on the other hand, it is weaker since strong time-consistency is not fully characterized. Finally, we exploit the relation between different notions of time-consistency.

Keywords

Cite

@article{arxiv.1512.03641,
  title  = {Time-consistency of cash-subadditive risk measures},
  author = {Elisa Mastrogiacomo and Emanuela Rosazza Gianin},
  journal= {arXiv preprint arXiv:1512.03641},
  year   = {2015}
}