Question

Let X1, X2,..., Xn be i.i.d. random variables from a double exponential distribution with density f(x) = 1/2*λ*exp(−λ|x|). Derive a likelihood ratio test of the hypothesis H0: λ=λ0 versus H1: λ=λ1, where λ0 and λ1 > λ0 are specified numbers. Is the test uniformly most powerful against the alternative H1: λ > λ0?

Answer 1

Mark rows downstream for 30 km, then turns around and returns to his original location. The total trip took 8 hr. If the current flows at 2 km/h, how fast would Mark row in still water?