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Management and experimentation

Run small experiments with a defined decision rule

A useful test starts with an uncertainty, a bounded change, and a written criterion before seeing the result.

Luiz Philipe (LP)

Luiz Philipe (LP)

Updated October 3, 2026

Run small experiments with a defined decision rule

Experiments lose value when the team changes too many things at once or redefines success after looking at the data. A simple protocol makes learning clearer, even when the result is inconclusive.

Write the hypothesis and mechanism

Use: “If we make [change] to [group], we expect to observe [sign] because [reason].” The reason matters: if the signal doesn't change, you can assess whether the hypothesis or mechanism was wrong.

Define the test

Choose a main change, the group or situation, the period and how to record observations. Define in advance which result would support the hypothesis, which would weaken it and which would require more information. In tests with few observations, treat patterns as clues, not statistical proof.

Include safety and effort limits

Determine how much time or resources the test may consume and what situation requires stopping early. If there is a risk to customers, data, safety, or quality, protect participants and stop when unexpected harm arises.

When finished, record what happened, what was not measured and the next decision: adopt, adjust, repeat or abandon. An experiment that reduces uncertainty can already be useful, even without confirming the idea.

Frequently asked questions

Do I need a control group?

It depends on the cost of a wrong conclusion and the test design. In simple cases, a before/after comparison can guide the next question, but it does not isolate all causes.

What if the result is inconclusive?

Review duration, quality of measurement and size of effect that you could perceive. Decide whether it is worth repeating with a better design or whether the remaining uncertainty is acceptable.

Can I test multiple changes?

It can in exploratory testing, but separate changes help to understand what influenced the result.

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