Bayesian Testing
01 Definition
Bayesian Testing meaning: An approach that reports the probability that a variant is the better option.
Bayesian testing combines prior belief with observed data to produce a probability that one variant beats another. Instead of a p-value, it answers questions like the chance the variant is best and the expected size of the improvement. It updates as data arrives, which many teams find easier to interpret.
Why it matters
How Bayesian Testing fits the work
Bayesian testing states results as plain probabilities of being better, which stakeholders often read more naturally than significance thresholds.
In context
The Bayesian test reported an 92 percent probability that the new headline outperformed the original, guiding the team to roll it out.
Practical note
Results can depend on the prior you choose, so a poorly set prior can bias conclusions. It still needs enough data, and continuous monitoring should follow the tool's stated rules.