Anomaly Investigation
Investigates a number that moved, ruling out instrumentation before looking for a business explanation.
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Running it, start to finish
- Confirm the period is complete and the comparison is fair.
- Rule out instrumentation before decomposing.
- Confirm the leading explanation with a check that could disprove it.
What you get back
The output this produces, every time.
- Rules out a partial period and a definition change before looking for a business cause.
- Decomposes ratios into numerator and denominator, which are opposite situations.
- Requires an explanation to account for the timing, size and segment shape, not just be plausible.
Getting better results
Where this usually goes wrong, and how to avoid it.
- Check the current period is complete. A partial week or late-arriving data is the most common false anomaly by a wide margin, and it costs an afternoon every time.
- Resist the business story. One is always available and always convincing. Sections 1 and 2 exist because the base rate says it is usually instrumentation.
- Look for a disconfirming check. Section 6 asks for one that could prove you wrong, which is the only kind that settles it.
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Written for The AI University. Every prompt in this library is original work — authored, tested and revised here, not collected from elsewhere. 365 of them, free with an account.