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THE FEUTEX TOOLKIT

Zero-Event Upper Risk Bound

Estimate a one-sided event-probability upper bound after observing no events.

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FormulaExact Upper = 1-alpha**(1/n); Rule Three = min(1,3/n)
Sources and model references

Made for real tasks

  • Estimate a one-sided event-probability upper bound after observing no events.
Explore step-by-step workflows →

Worked example

Inputs

Independent trials with zero events
100 count
One-sided alpha
0.05 probability

Expected results

Exact Upper
0.02951304961 probability
Rule Three
0.03 probability

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter independent trials with zero events, one-sided alpha.
  2. Use the displayed units and confirm the model assumptions.
  3. Calculate and compare the outputs against your input scenario.

Try this example

{
  "n": 100,
  "alpha": 0.05
}

Accuracy and scope

Exact bound assumes independent identical Bernoulli trials with zero observed events. Rule of three is a 95% approximation only.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.