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arXiv · 1608.05585

Consistency of option prices under bid-ask spreads

Stefan Gerhold·I. Cetin Gülüm
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Abstract

Given a finite set of European call option prices on a single underlying, we want to know when there is a market model which is consistent with these prices. In contrast to previous studies, we allow models where the underlying trades at a bid-ask spread. The main question then is how large (in terms of a deterministic bound) this spread must be to explain the given prices. We fully solve this problem in the case of a single maturity, and give several partial results for multiple maturities. For the latter, our main mathematical tool is a recent result on approximation by peacocks [S. Gerhold, I.C. G\"ul\"uum, arXiv:1512.06640].

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Stefan Gerhold, I. Cetin Gülüm. 2016-08-19. Consistency of option prices under bid-ask spreads. https://arxiv.org/abs/1608.05585

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