Recall that an exponential (λ) random variable X has
Thus, to estimate λ from n independent samples X1,..., Xn, either of the following techniques should work.
(a) Calculate the sample mean Mn (X) and form the estimate λˆ = 1/Mn(X).
(b) Calculate the unbiased variance estimate V'n(X) of Theorem 7.11 and form the estimate λ = 
Use Matlab to simulate the calculation 
and for m = 1000 experimental trials to determine which estimate is better.