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5. Concepts of Stochastic Convergence  275

                                    tλ
                           nλe } → e  as n → ∞.}
                              t/n
                              5.3.1 (Exercise 5.2.1 Continued) Find a and b(> 0) such that we can
                           claim:                       as n → ∞.
                              5.3.2 (Example 5.3.5 Continued) Let X , ..., X  be iid Uniform (0, θ)
                                                                       n
                                                                 1
                           with θ > 0 and suppose that T  = X , the largest order statistic. First, find
                                                     n
                                                         n:n
                           the df of the random variable G  = n(θ – T )/T , and then use the Definition
                                                                  n
                                                               n
                                                      n
                           5.3.1 to show directly that the limiting distribution of G  is the standard
                                                                             n
                           exponential.
                              5.3.3 Prove CLT using the mgf technique assuming that the X’s are iid having
                                                                              i
                           a finite mgf for | t |< h with some h > 0. {Hint: Follow the derivations in Examples
                           5.3.3-5.3.4 closely.}
                              5.3.4 (Example 5.3.7 Continued) Under the same conditions as the CLT, along
                           the lines of Example 5.3.7, derive the asymptotic distribution of
                                (i)                 as n → ∞ if µ ≠ 0;
                                (ii)                  as n → ∞ if µ > 0 and     is positive w.p.1.
                           In this problem, avoid using the Mann-Wald Theorem.
                              5.3.5 (Exercise 5.3.2 Continued) Let X , ..., X  be iid Uniform (0, θ) with
                                                                    n
                                                              1
                           θ > 0 and suppose that T  = X , the largest order statistic. Does n{θ –
                                                      n:n
                                                  n
                                       converge to some appropriate random variable in distribution as
                           n ? ∞? {Hint: Can Slutsky’s Theorem be used here?}
                              5.3.6 (Exercise 5.2.3 Continued) Let X , ..., X  be iid N(µ, 1), –∞ < µ < ∞.
                           Consider the following cases separately:  1  n



                              Find suitable a , b  (> 0) associated with each T  such that
                                          n  n                       n
                           N (0, 1) as n → ∞. {Hint: Is the Mann-Wald Theorem helpful here?}
                              5.3.7 (Example 5.3.8 Continued) Find the number  η  ( > 0) such that
                                                  as n → ∞. Here,     is the sample variance obtained from iid
                           random variables X , ..., X , n ≥ 2. Solve this problem separately when the X’s are (i)
                                                                                     i
                                         1
                                              n
                           normal and (ii) non-normal, under appropriate moment assumptions. {Hint: Is the
                           Mann-Wald Theorem helpful here?}
                              5.3.8 (Exercise 5.3.7 Continued) Find the number η( > 0) such that
                                                   N(0, η ) as n → ∞, where u (≠ 0) is some fixed
                                                        2
                           real number. Hence, that is without referring to Slutsky’s Theorem, find the
                           number ξ(> 0) such that                           as  n  → ∞ where
                           u (≠ 0) is some fixed real number. Solve this problem separately when
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