where c is the indierence price. The marginal optimal hedge H is dened as the
derivative of G w.r.t. q at q = 0. Hence, the denition of the marginal optimal
hedge presented here is based on the same idea as the denition of Kramkov
and S^rbu.
Let us see whether the two notions coincide in the case of power utility. By
[9, Thm. 1], the process H is given by (for initial capital x = 1)