Question

6. Let S(t) denote the price of a security at time t. A popular model for the process S(t): t 0} supposes that the price remains unchanged until a "shock" occurs, at which time the price is multiplied by a random factor. If we let N(t) denote the number of shocks by time t, and let Xi denote the ith multiplicative factor then this model supposes that N (t) "x II (0)s ()s

Answer 1

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