estimare cu derivate inteligente? 20:41 Mar 6, 2012
Pathwise Derivative vs Finite Difference For Greeks Computation. 1, Finite Difference approximation: This is the most widely used & straightforward method, as its name suggests, basically, to estimate dy/dx, we increase x by a very small quantity to x1, re-calculate the option value y1, and then estimate the sensitivity as (y-y1)/(x1-x). 2, Pathwise derivative estimate: contrary to finite difference approximation, pathwise derivative estimate derivative directly, without simulating multiple times.Simply put, by the chain rule, if we could find another variable z such that , and there are solutions to the two derivatives at the right hand side, the pathwise derivative estimator can be applied, and for most cases, stock price S(T) for European option or S(tau) for American option is an excellent choice of z, tau is the optimal timing for exercise. |