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Creative test post-mortem: did the winner really win?

The test 'has a winner' and everyone wants to scale it. Interrogate the result before it becomes the new control.

The prompt — copy and run it

You are an experimentation-minded media analyst reviewing a creative or copy test. I will paste the setup and results. Produce:

A) A VERDICT — real win, suggestive, or UNREADABLE — with plain-language reasoning about sample size, effect size, and duration using my numbers. Do not fabricate p-values or significance claims; if a statistical read is impossible from what I gave you, state exactly which input is missing.
B) A CONFOUND CHECK: novelty effect, uneven delivery or auction mix between variants, audience overlap, and day-of-week skew — each with the specific report or breakdown in my platform that would confirm or clear it.
C) NEXT STEP: if the win is real, the scale plan with a creative-fatigue watch metric; if unreadable, the redesigned test with the specific fix that makes it readable.

My test: [PASTE: variants, split method, duration, per-variant spend/impressions/results, how the platform declared the winner]

Rules: Do not invent, estimate, or fabricate any statistic, benchmark, or performance figure — if a number is not in the material I give you, write "not provided" and flag it. Mark every claim I should verify in my analytics or source systems before it is published or presented. Never include customer personally identifiable information or client-confidential terms.

How to use this prompt

  1. Copy the full prompt above with the Copy button.
  2. Add your context. This prompt runs as-is — paste it, then add the specific details, data, or files it should reason over.
  3. Paste into ChatGPT, Claude, or Gemini and run. Read the reality guardrail below before you act on the output.

Why this prompt works

Ad platforms declare winners with confidence the underlying data rarely earns. A post-mortem that is allowed to return 'unreadable' protects the account from installing noise as the new control — the most expensive quiet mistake in paid media, because every future test inherits it.

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Reality guardrail: this prompt makes the model reason from data you paste — it does not source or verify facts for you. Check every claim, keep confidential data out of consumer AI tools, and follow your employer's AI-use policy.

Frequently asked

When should I use this prompt?

The test 'has a winner' and everyone wants to scale it. Interrogate the result before it becomes the new control.

Why does this prompt work?

Ad platforms declare winners with confidence the underlying data rarely earns. A post-mortem that is allowed to return 'unreadable' protects the account from installing noise as the new control — the most expensive quiet mistake in paid media, because every future test inherits it.

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PromptSharp prompts are drafted with AI assistance and human-reviewed. They structure how a model reasons over data you provide — they do not source or verify facts for you, and you own every output. Nothing here is financial, legal, tax, or investment advice. Never paste confidential, client, or material non-public information into consumer AI tools; follow your employer's AI-use policy. © 2026 PromptSharp.