Bootstrap CI methods — percentile vs BCa vs studentized.
hardAnswer
- Percentile: use 2.5th and 97.5th quantiles of bootstrap distribution — simple but biased when the sampling distribution is skewed.
- BCa (bias-corrected & accelerated): corrects bias and skewness → generally best default.
- Studentized (bootstrap-t): asymptotically most accurate but requires an SE estimate per bootstrap sample.
- Basic (pivotal): 2*θ̂ - , 2*θ̂ - .
- Rule: default BCa; percentile only if you know the sampling distribution is symmetric.
Check yourself — multiple choice
- Only percentile
- Percentile (biased under skew) / BCa (bias + skew corrected — default) / studentized (best asymptotically) / basic — BCa is safest default
- Same as t-CI
- Only Bayesian
Bootstrap CI: BCa default; percentile only if symmetric; studentized most accurate but costly.
#bootstrap#confidence-interval
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