=+14.3. Consider the example of sample mean discussed below (14.1). Showed that, in this case, the right side of (14.8) is equal to s2/n, where s2 = (n −

1)−1 n i=1(Xi − X¯ )2 is the sample variance. Therefore, we have E{var ; J(ˆθ)} =

var(ˆθ); in other words, the jackknife variance estimator is unbiased.