Baseline window

The baseline window is the before state of the experiment.

It shows what prompts, answers, sources, and competitors looked like before the change. Without it, the experiment result is hard to judge.

Clean baseline period

Use a clean period before the main change.

The baseline does not need to be perfect. It needs to be clear enough to compare. Avoid using a period where many unrelated changes happened.

Baseline window

The baseline is the before state for mentions, answer wording, sources, and competitors.

Data before start

Look for the main signals before the experiment begins.

SignalBaseline question
MentionsWas your brand named before the change?
SourcesWhich pages were read before the change?
CompetitorsWho appeared before the change?
Answer wordingHow did the answer explain the topic?

Measurement effect

The baseline keeps the test honest.

If results improve later, the baseline helps explain what changed. If results do not improve, it helps show whether the test was too small, too early, or pointed at the wrong question.

Protect comparison

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