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Donnu A/B Blog

Complete, honest guides on CRO, A/B testing and experimentation. The most complete articles on the web, no fluff. (page 14 of 17)

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Multi-Armed Bandits for Pricing Tests (2026)

Multi-armed bandits for pricing tests: protect margin with revenue per visitor as the metric, and know when a classic A/B test still wins.

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Region of Practical Equivalence (ROPE) in A/B Testing

The region of practical equivalence (ROPE) is a Bayesian rule for calling a lift too small to matter, even when it is technically real.

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Credible Interval vs Confidence Interval

Credible interval vs confidence interval: the real difference between the Bayesian and frequentist reading of the same range, with a full numeric example.

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Expected Loss in Bayesian A/B Testing

Expected loss in Bayesian A/B testing measures how much a wrong call would cost, not just the odds of being right. Worked example inside.

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Sequential Testing in A/B: Peek Anytime, Explained (2026)

Sequential testing A/B: how always-valid inference (mSPRT) lets you peek at results anytime without inflating false positives, and when it pays off.

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Bayesian Priors Explained: A/B Testing Guide

Bayesian priors in A/B testing explained with real numbers: informative vs uninformative priors, how each reshapes the posterior, and when to use each.

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Thompson Sampling Explained: Bandit Algorithm

Thompson sampling explained: how it draws from each arm's Beta posterior and why it converges faster than epsilon-greedy, with a worked example.

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What Is CUPED? Reducing A/B Test Variance

CUPED is a variance reduction technique that uses pre-experiment data to shorten A/B test duration without losing statistical rigor.

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What Is a Contextual Bandit? (vs. A/B Testing)

Learn what a contextual bandit is, how it differs from a simple multi-armed bandit, and when it earns its added complexity over A/B testing.