Risk measures on incomplete markets: a new non-solid paradigm

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Melnikov, Vasily
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917906320719872
author Melnikov, Vasily
author_facet Melnikov, Vasily
contents We study risk measures $φ:E\longrightarrow\mathbb{R}\cup\{\infty\}$, where $E$ is a vector space of random variables which a priori has no lattice structure$\unicode{x2014}$a blind spot of the existing risk measures literature. In particular, we address when $φ$ admits a tractable dual representation (one which does not contain non-$σ$-additive signed measures), and whether one can extend $φ$ to a solid superspace of $E$. The existence of a tractable dual representation is shown to be equivalent, modulo certain technicalities, to a Fatou-like property, while extension theorems are established under the existence of a sufficiently regular lift, a potentially non-linear mechanism of assigning random variable extensions to certain linear functionals on $E$. Our motivation is broadening the theory of risk measures to spaces without a lattice structure, which are ubiquitous in financial economics, especially when markets are incomplete.
format Preprint
id arxiv_https___arxiv_org_abs_2409_05194
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Risk measures on incomplete markets: a new non-solid paradigm
Melnikov, Vasily
Risk Management
Functional Analysis
Probability
Mathematical Finance
46E30, 46N30, 91G70
We study risk measures $φ:E\longrightarrow\mathbb{R}\cup\{\infty\}$, where $E$ is a vector space of random variables which a priori has no lattice structure$\unicode{x2014}$a blind spot of the existing risk measures literature. In particular, we address when $φ$ admits a tractable dual representation (one which does not contain non-$σ$-additive signed measures), and whether one can extend $φ$ to a solid superspace of $E$. The existence of a tractable dual representation is shown to be equivalent, modulo certain technicalities, to a Fatou-like property, while extension theorems are established under the existence of a sufficiently regular lift, a potentially non-linear mechanism of assigning random variable extensions to certain linear functionals on $E$. Our motivation is broadening the theory of risk measures to spaces without a lattice structure, which are ubiquitous in financial economics, especially when markets are incomplete.
title Risk measures on incomplete markets: a new non-solid paradigm
topic Risk Management
Functional Analysis
Probability
Mathematical Finance
46E30, 46N30, 91G70
url https://arxiv.org/abs/2409.05194