CRO Glossary
Hypothesis Statement
A structured prediction used to design an experiment, typically framed as a change, an expected effect, and the reasoning behind it.
A hypothesis statement turns a hunch into something testable. A common format is: 'If we [make this change], then [this metric] will [increase/decrease], because [reasoning grounded in user behavior or data].' Writing it this way forces the team to be explicit about what they expect to happen and why, which makes it much easier to interpret results afterward, whether the test confirms, contradicts, or is inconclusive relative to the prediction.
Good hypotheses are grounded in evidence: session recordings, funnel analysis, support tickets, or heuristic review, rather than a random idea. This grounding also helps prioritize which tests to run first, since experiments backed by strong qualitative or quantitative signals tend to have a higher hit rate.
For example, a weak hypothesis might be 'let's try a red button.' A strong one is: 'If we change the CTA button color from gray to a high-contrast orange, then click-through rate on the pricing page will increase, because session recordings show users hovering over the button without clicking, suggesting it isn't visually distinct enough from the surrounding page.' The explicit reasoning also makes it easier to design a good guardrail metric set, since you can anticipate likely side effects.
Related terms
Above vs Below Median Split
A segmentation technique that divides users into two groups at the median of a metric to compare high and low engagers.
Qualitative Feedback Loop
A recurring process of collecting and acting on user comments, session recordings, and survey responses to inform test hypotheses.
Experiment Metadata
The structured record of who, what, when, and how for a test — hypothesis, owner, dates, variants, and metrics used to track and audit it.
Pre-Test Analysis
The upfront work of validating traffic, metrics, and baseline data quality before launching an experiment.
Above-the-Fold vs Below-the-Fold Messaging Hierarchy
How the order and prominence of value-proposition messaging is split between the visible screen and the rest of the page.
Experiment Contamination
When a control or variant group is unintentionally exposed to the other condition, corrupting the comparison.
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