Bayesian A/B testing estimates the probability that a variant outperforms the control and expresses uncertainty as a credible interval instead of relying on a single lift number.

Chance to beat control

This probability answers a direct decision question, but it does not tell you whether the likely improvement is large enough to justify rollout.

Credible intervals

The interval shows a plausible range for the effect. Wide intervals warn that the estimate is still uncertain even when the displayed lift looks attractive.

Make a business decision

Combine probability, effect size, downside risk, runtime, traffic mix, and implementation cost. The strongest statistical variant is not always the best operational choice.

Run the test in Shopify

Sofcy supports URL, template, theme, and custom JavaScript API experiments.

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