|Date: Friday, March 11, 2016
Location: 1866 East Hall (4:00 PM to 5:00 PM)
Title: Economically consistent valuations and put-call parity
Abstract: We propose an approach to the valuation of contingent claims in general, symmetric
semimartingale models of financial markets. We start from two simple, economically
motivated axioms, namely absence of arbitrage (in the sense of NUPBR) and absence of relative arbitrage among all buy-and-hold strategies (called static efficiency). We then call a valuation process for a contingent claim economically
consistent if the financial market enlarged by that process still satisfies this combination
of properties. It turns out that this approach lies in the middle between the
extremes of valuing by risk-neutral expectation or by absence of arbitrage alone.
We show that this always yields put-call parity, although put and call values themselves
can be nonunique, even for complete markets. We provide general formulas
for put and call values in complete markets and show that these are symmetric and
that both contain in general three terms. We also show that our approach contains
all the put-call parity respecting valuation formulas in the classic theory as special
cases, and we explain precisely when and how the different terms in the put and
call valuation formulas disappear or simplify.
Joint work with Martin Schweizer.
Speaker: Martin Herdegen
Event Organizer: Erhan Bayraktar email@example.com