There are many different kinds of rainbow options, suppose you are talking about an option on the maximum or minimum stock return of a basket.
Delta hedging is a standard way. Each stock will have a delta which will be approximately equal to (plus or minus) its probability, under the risk-neutral distribution, of being the maximum (or minimum).
The problem for delta hedging is as time approaches zero you find delta of one stock approaching 1 (or -1) while the others approach zero. This is fine actually, but if there is a barrier, delta hedging breaks down because it will become so unstanble when underlying asset approaching barrier.
Aonther problem is the parameter of correlation matrix, it is so tricky that no one can asure you can get correct estimates. The best way I think is to find out similar products to backout implied correlation, and do some statistics to come up with a reasonable spread.
I agree with upstairs that static hedge with uncertain parameter is a solution to aforementioned problem(hard to explain details here, all in CQF). Static hedge with multiple underlying is no difficult than single underlying, simply including vanilla options with each underlying.
[ 本帖最后由 EnglandWhite 于 2008-2-1 03:18 AM 编辑 ]