Why do you need block bootstrap for time series?
hardAnswer
- Standard bootstrap resamples individual points, destroying temporal dependence and grossly under-estimating variance for autocorrelated data.
- Block bootstrap resamples contiguous blocks (moving or stationary) to preserve short-range dependence.
- Block length L chosen so autocorrelation dies within L .
- Foundational for CIs in time-series metrics, hedge-fund performance, drift detection.
Check yourself — multiple choice
- Same as regular
- Standard bootstrap destroys temporal correlation → understates variance; block bootstrap resamples contiguous blocks preserving short-range dependence
- Only for regression
- Not needed
Block bootstrap: preserves temporal correlation via contiguous blocks.
#bootstrap#confidence-interval
Practise Statistics Fundamentals
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