
Chapter 10
McKean Nonlinear Stochastic
Differential Equations
The advantage of being smart is that you can always make a fool,
while the opposite is quite impossible.
— Woody Allen
As will be explained in Chapters 11 and 12, the calibration of local stochastic
volatility models and local correlation models to market smiles leads to the
so-called McKean nonlinear stochastic differential equations (SDEs). In such
nonlinear SDEs, in contrast with classical Itˆo SDEs, the drift and volatil-
ity coefficients depend on the (unknown) marginal law of the process. The
Fokker-Planck equation associated to this SDE is therefore nonlinear, hence
the denomination. In