When determining the SDE of St I can't see where the '- lambda sigma term' comes from. The report says change the Brownian motion and the probability measure using the CMG theorem. I can get there working backwards because I know the drift must be 0 but I don't think thats the right way to go about it. Please could someone explain further?
I did ask the same question when taking CT8 a little while ago. If I recall, lambda is a typo and shouldn't be there. Drop Cm2@bpp.com an email and hopefully they can send you a correct solution.
