Formula (2.3) has alternative formula X2 = n(ij i++j )2/i++j . Explain why, for particular {ij},

Formula (2.3) has alternative formula X2 = n(ˆπij − πˆi+πˆ+j )2/πˆi+πˆ+j . Explain why, for particular {πˆij}, X2 is large when n is sufficiently large, regardless of whether the association is practically important. Hence, chi-squared tests merely indicate the degree of evidence against a hypothesis and do not describe the strength of association.