(‡) n1] = n1 k − n (x)|N1(x) = (j + 1)E[R1j (x)|N1(x) = n k k n1] E[ xi|N1(x) = n1] − − − j=k i=n−k+1 That holds can be confirmed by first noting that, on the left hand side, ( ) is a divisor within ‡ n each conditional expectation, and therefore can be canceled, which yields a ratio in which the
(x)|N1(x) = n1] n = n1 − k (‡) j=k (j − k + 1)E[R1j (x)|N1(x) = n1] − E[ i=n−k+1 xi|N1(x) = n1] n − k That ‡ holds can be confirmed by first noting that, on the left hand side, ( n ) is a divisor within each conditional expectation, and therefore can be canceled, which yields a ratio in which the