Bootstrap Mean Confidence Interval Calculator
Generate a reproducible percentile bootstrap interval for a sample mean, with bootstrap standard error, bias and empirical quantiles.
YOUR CALCULATION
Result
β
Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Draw equal-size samples with replacement from the empirical sample and use linearly interpolated percentiles of the replicate means.
Percentile interval=[q*(Ξ±/2),q*(1βΞ±/2)]
Worked example
For a constant sample 10,10,10, every resampled mean is exactly 10 and the interval is [10,10]. For varying data the reported endpoints depend on the displayed seed and finite resample count.
Assumptions and input details
2β200 observations and 200β5000 resamples, at most one million draws. Seed uses a deterministic 32-bit generator for reproducibility, not cryptography. This implements the percentile method, not BCa, studentized or exact coverage. Independent representative sampling is an external assumption. Monte Carlo error, small samples and heavy tails can materially affect interval behavior.
References: SciPy: percentile bootstrap method and assumptions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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