Bi-revealed utilities in a defaultable universe : a new point of view on consumption. - Archive ouverte HAL
Pré-Publication, Document De Travail (Preprint/Prepublication) Année : 2022

Bi-revealed utilities in a defaultable universe : a new point of view on consumption.

Résumé

This paper investigates the inverse problem of bi-revealed utilities in a defaultable universe, defined as a standard universe (represented by a filtration $\bF$) perturbed by an exogenous defaultable time $\tau$. We assume that the standard universe does not take into account the possibility of the default, thus $\tau$ adds an additional source of risk. The defaultable universe is represented by the filtration $\bG$ {\it up to time $\tau$}, where $\bG$ stands for the progressive enlargement of $\bF$ by $\tau$. The basic assumption in force is that $\tau$ avoids $\bF$-stopping times. The bi-revealed problem consists in recovering a consistent dynamic utility from the observable characteristic of an agent. The general results on bi-revealed utilities, first given in a general and abstract framework, are translated in the defaultable $\bG$-universe and then are interpreted in the $\bF$-universe. The decomposition of $\bG$-adapted processes provides an interpretation of a $\bG$-characteristic $X^\bG_\tau$ stopped at $\tau$ as a reserve process. Thanks to the characterization of $\bG$-martingales stopped at $\tau$ in terms of $\bF$-martingales, we establish a correspondence between $\bG$-bi-revealed utilities from characteristic and $\bF$-bi-revealed pair of utilities from characteristic and reserves. In a financial framework, characteristic can be interpreted as wealth and reserves as consumption. This result sheds a new light on the consumption in utility criterion: the consumption process can be interpreted as a certain quantity of wealth, or reserves, that are accumulated for the financing of losses at the default time.
Fichier principal
Vignette du fichier
BiRevealedDefaultableFinal.pdf (546.87 Ko) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)
Licence
Copyright (Tous droits réservés)

Dates et versions

hal-03919186 , version 1 (02-01-2023)

Licence

Copyright (Tous droits réservés)

Identifiants

  • HAL Id : hal-03919186 , version 1

Citer

El Karoui, Mrad Mohamed, Caroline Hillairet. Bi-revealed utilities in a defaultable universe : a new point of view on consumption.. 2022. ⟨hal-03919186⟩
121 Consultations
60 Téléchargements

Partager

More