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Interpreting Wide Confidence Intervals

HardA/B Testing & Experimentation00:00
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Your question is Interpreting Wide Confidence Intervals. Take a moment with it on the right.

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Problem

Scenario

You run an A/B test on a growth surface in a business software product, and the treatment shows a positive lift on the primary conversion metric. However, the confidence interval is wide, so the estimate ranges from a small win to a much larger one, and stakeholders are pushing to call the experiment successful.

Question

What would you do if an experiment had a positive result but the confidence interval was wide? How would you decide whether the result is actionable enough to ship, extend, or rerun?

What This Tests

  • Interpretation of confidence intervals
  • Use of MDE to judge actionability
  • Guardrail-aware ship decisions
  • Awareness of peeking and SRM