In Problems 58-64 you will show that the univariate t-statistic has a t-distribution with n − 1 degrees of freedom when
Posted: Tue Jul 05, 2022 9:20 am
In Problems 58-64 you will show that the univariate t-statistic has a t-distribution with n − 1 degrees of freedom when the population is normal. For these problems, suppose that X₁,..., Xn are iid N (μ, o2). It is possible to construct a nonrandom nxn matrix A with columns A₁,..., An such that A₁ = (1/√n,...,1/√√n)' and A'A = AA' = In where In is the n x n identity matrix. We will not prove this fact, but will assume that A is such a matrix. Note that for any i, j in {1,...,n}, Aj Aj = 0 if i j, and A; Ai 1. Define the vector X let Z = A'X, so that Z is an n-dimensional column vector, Z = (Z₁,,Zn)'. We can write (X₁, Xn)' and n X = Σj=1 AjZj. 58. Show that Z₁ = √n X. = =