This article surveys bootstrap methods for producing good approximate
confidence intervals. The goal is to improve by an order of magnitude
upon the accuracy of the standard intervals <(theta)over cap> +/- z((a
lpha))<(sigma)over cap>, in a way that allows routine application even
to very complicated problems. Both theory and examples are used to sh
ow how this is done. The first seven sections provide a heuristic over
view of four bootstrap confidence interval procedures: BCa, bootstrap-
t, ABC and calibration. Sections 8 and 9 describe the theory behind th
ese methods, and their close connection with the Likelihood-based conf
idence interval theory developed by Barndorff-Nielsen, Cox and Reid an
d others.