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This content will become publicly available on April 28, 2026

Title: Representation of indifference prices on a finite probability space
On a finite probability space, we consider the problem of indifference pricing of contingent claims, where the preferences of an economic agent are modeled by an Inada utility stochastic field — the interior of its effective domain being (a,∞) — for some a∈R∪{−∞}. This allows for including utilities on both R and R+. We consider arbitrary contingent claims and show that, for replicable ones, the indifference price equals the initial value of the replicating strategy and thus depends neither on the agent’s initial wealth, for which the indifference pricing problem is well-posed, nor the utility stochastic field. This, in particular, shows the consistency of the indifference and arbitrage-free pricing methodologies for complete models. For nonreplicable claims, we show that the indifference price is equal to the expectation of the discounted payoff under the dual-optimal measure, which is equivalent to the reference probability measure. In particular, we demonstrate that the indifference price is unique for every choice of a smooth Inada utility stochastic field and initial wealth in (a,∞). Our proofs rely on the change of numéraire technique and a reformulation of the indifference pricing problem. The advantages of the settings of this paper and the approach allow for bypassing the technicalities and issues related to choosing the notion of admissibility and for including a wide range of utilities, including stochastic ones. We augment the results with examples.  more » « less
Award ID(s):
1848339
PAR ID:
10594298
Author(s) / Creator(s):
; ;
Publisher / Repository:
Mathematical Sciences Publishers
Date Published:
Journal Name:
Involve, a Journal of Mathematics
Volume:
18
Issue:
3
ISSN:
1944-4176
Page Range / eLocation ID:
495 to 516
Subject(s) / Keyword(s):
indifference pricing, incomplete markets, duality, numeraire.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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