Jackknife standard error from leave-one-out estimates

You estimate a statistic by the jackknife: with $n = 4$ observations, you delete one point at a time and recompute the statistic on the remaining three, giving four leave-one-out estimates:

$\hat{\theta}_{(1)} = 10, \quad \hat{\theta}_{(2)} = 12, \quad \hat{\theta}_{(3)} = 14, \quad \hat{\theta}_{(4)} = 16.$

Compute the jackknife estimate of the standard error.