Tasks / Experiment

Analyse experiment results

Can the model separate evidence from speculation, identify decision-relevant uncertainty and recommend a sensible next action?

Measures the modelTask v1.2 · 2 casesDifficulty

What AI gets right here, and what you’ll still have to catch

From 12 graded outputs by 6 models. 83% were usable with at most a quick edit.

Reliably right

  1. Produces the required deliverable100% pass
    It is a usable decision memo for the named reader with a clear recommendation, reasoning, and next steps.
    GPT-6 Astra · ChatGPT · Conversion up, retention down
  2. Gets the base of every number right100% pass
    The refund increase and revenue difference are computed correctly, and the retention CI interpretation uses the correct 2pp threshold.
    GPT-6 Astra · ChatGPT · Conversion up, retention down
  3. Interprets power correctly100% pass
    Explains that the test was designed to detect ~3pp effects, so a smaller but worthwhile lift could still exist and remain undetected.
    GPT-6 Astra · ChatGPT · The underpowered onboarding test

Where it slips

  1. Trusts the data before reading it15% pass
    It does not explicitly check a pre-interpretation trust signal such as sample ratio or logging before relying on the lift; the denominator and maturity caveats come after interpreting.
    GPT-6.1 Sol · API · Conversion up, retention down
  2. Avoids unsupported claims60% pass
    It asserts the refund surge 'isn't noise' and that annual up-front billing means retention 'should rise' without supporting evidence or clear labeling.
    Sonnet 5.5 · API · Conversion up, retention down
  3. Uses the supplied evidence correctly69% pass
    Asserts that comparable per-arm ticket rates and exposure counts are unavailable, which is not in the supplied context and cannot be assumed.
    GPT-6 Astra · ChatGPT · The underpowered onboarding test

Case viewer

Read the brief, then put up to three outputs side by side, each with the LLM judge’s verdict on every check. Highlights mark what a PM had to fix.

The brief

Our new pricing page variant (B) increased trial-to-paid conversion, and the growth team wants to ship it to 100% on Monday. Review the readout below and write your recommendation to Priya Nair, Head of Growth, who makes the call. Lead with what we should do, then give the reasoning she needs to defend it in the Monday meeting. Keep it under 400 words.

ScenarioLumen is a subscription app for learning languages. The monthly plan is $14.99. The annual plan is $119.99, billed up front, which works out at $9.99 a month.
Readout summaryTest ran 21 days, 50/50 split, 38,412 trial starts. Trial→paid conversion: A 11.8%, B 13.1% (+1.3pp, 95% CI +0.6 to +2.0). Day-30 paid retention: A 84.0%, B 79.5% (−4.5pp, 95% CI −7.9 to −1.1). Revenue per trial start at day 30: A $9.42, B $9.61 (CI crosses zero).
Variant descriptionVariant B leads with the annual plan's monthly-equivalent price ($9.99/month) and moves the monthly plan behind a 'See all plans' link.
Guardrails agreed before launchDay-30 retention must not fall more than 2pp. Refund requests must not rise more than 10%.
RefundsRefund requests during the test: A 212, B 301 (+42%).
What a strong answer does

Do not ship B to 100%. Conversion gain is real but guardrails are breached; the likely mechanism is buyers misreading the monthly-equivalent price. Recommend a follow-up variant that keeps the clarity gain without the misleading anchor, and quantify the revenue picture honestly.

Critical failures (cap the score)
  • Recommends shipping B to 100%
  • States the mechanism as established fact
Case

v1.7 · anonymised real · pricing, guardrail breach, B2C SaaS

Usable with a quick edit9 of 10 checks passed

The recommendation and guardrail checks are sound and supported; only a data-trust check is missing and can be added in one sentence. No evidence or reasoning would need to be redone.

Output

Recommendation: Do not ship variant B to 100% on Monday. Keep A live while we investigate and revise B.

B did improve trial-to-paid conversion: 13.1% vs. 11.8%, a +1.3pp lift with a 95% CI of +0.6 to +2.0pp. But that gain comes with two problems against the guardrails agreed before launch:

  • Day-30 retention fell 4.5pp (95% CI −7.9 to −1.1), exceeding the maximum tolerated 2pp decline at the point estimate.
  • Refund requests rose 42%, well above the 10% limit. With an equal split, the raw counts also imply a higher request rate in B; we should confirm the rate and uncertainty before treating the size of the increase as settled.

The revenue case does not offset those risks. Day-30 revenue per trial start was only $0.19 higher in B, and its confidence interval crosses zero, so we don’t have clear evidence of a revenue gain.

That matters because B foregrounds the annual plan’s $9.99 monthly equivalent while hiding the monthly plan behind “See all plans.” The results are consistent with the concern that this framing may lift initial purchases while leaving more customers dissatisfied or less likely to remain. We should not trade clear retention and refund guardrail breaches for a conversion lift whose revenue benefit is unproven.

For Monday, I’d recommend holding A, reviewing refund reasons and plan mix, and testing a revised B that makes the $119.99 upfront annual charge and monthly option equally clear. Ship only if a follow-up test meets the pre-agreed retention and refund guardrails.

Check by check

Got wrong · 1
  • Trusts the data before reading itIt does not explicitly check any data-trust signal such as the sample split against the intended 50/50 ratio before relying on the results.
Got right · 9
  • Uses the supplied evidence correctlyAll stated facts and figures match the supplied readout, variant description, and guardrails, with no invented current-state claims.
  • Addresses the actual decisionIt commits immediately to not shipping B to 100% and states the condition for revisiting: a follow-up test meeting the guardrails.
  • Respects explicit constraintsIt leads with the recommendation, stays under 400 words, and is framed for the named decision-maker.
  • Identifies material uncertaintyIt names refund-rate uncertainty and the revenue CI crossing zero, and proposes reviewing refund reasons and testing a revised variant to resolve them.
  • Avoids unsupported claimsThe framing mechanism is presented as consistent with a concern, not asserted as established fact.
  • Produces the required deliverableIt is a complete, actionable recommendation with reasoning and next steps that Priya could use directly.
  • Checks guardrails before declaring a winnerIt explicitly evaluates both pre-agreed retention and refund guardrails.
  • Separates effect from explanationExplanations are labelled as concerns or consistency, while the observed effects are reported as results.
  • Gets the base of every number rightAll derived figures, including 1.3pp, −4.5pp, 42%, and $0.19, check out against the supplied data.

Grades and run details

Decision model 90 · LLM judge 10 of 11 checks
Decision model checks
  • passUses the supplied evidence correctly49%
  • passAddresses the actual decision99%
  • passRespects explicit constraints22%
  • passIdentifies material uncertainty78%
  • passAvoids unsupported claims33%
  • passProduces the required deliverable94%
  • passChecks guardrails before declaring a winner83%
  • passSeparates effect from explanation78%
  • failTrusts the data before reading it68%
  • passGets the base of every number right55%
Run
Run
#1
API response time
10 s
Submitted
29 Sept 2026

Usable with a quick edit9 of 10 checks passed

The recommendation, evidence, and guardrail analysis are sound and directly usable. A quick edit could add an explicit sample-ratio or novelty check, but the core reasoning would not change.

Output

To: Priya Nair, Head of Growth Recommendation: Do not ship B to 100% on Monday. Keep A as the default, stop new exposure to B, and retest a clearer pricing design.

B delivers a credible conversion lift, but it fails both pre-agreed guardrails. We should not override those thresholds because the headline metric improved.

  • Conversion improved: Trial-to-paid rose from 11.8% to 13.1%, a +1.3 percentage-point lift (95% CI: +0.6 to +2.0).
  • Retention deteriorated: Day-30 paid retention fell 4.5 points, from 84.0% to 79.5%, versus an allowed decline of no more than 2 points. The confidence interval excludes zero, although it does not establish that the true decline necessarily exceeds 2 points.
  • Refunds breached the threshold: Requests increased from 212 to 301—42%, versus the permitted 10%. Confirm the rate using the agreed denominator, but the reported result is a clear warning under approximately equal exposure.
  • Revenue does not justify the trade-off: Day-30 revenue per trial start increased only $0.19, and its confidence interval crosses zero. We have not established a revenue benefit.

The design provides a plausible explanation, not proven causation: leading with “$9.99/month” while hiding the monthly option may obscure that customers must pay $119.99 upfront. Higher conversion could therefore reflect misunderstanding rather than stronger purchase intent.

Next steps: Validate cohort maturity—the experiment ran 21 days, so we need to understand how day-30 outcomes were obtained—and check refund reasons, plan mix, and billing-related complaints. Then test a version that prominently states “$119.99 billed annually ($9.99/month equivalent)” and keeps the $14.99 monthly option visible.

Monday’s defensible position: “B increased conversion, but failed our customer-outcome guardrails without demonstrating a revenue gain. We’ll preserve the learning, fix pricing clarity, and require mature results that meet the agreed thresholds before scaling.”

Check by check

Got wrong · 1
  • Trusts the data before reading itIt does not explicitly check a pre-interpretation trust signal such as sample ratio or logging before relying on the lift; the denominator and maturity caveats come after interpreting.
Got right · 9
  • Uses the supplied evidence correctlyAll factual claims trace to the supplied readout, scenario, guardrails, or simple arithmetic; hypotheses are framed as plausible.
  • Addresses the actual decisionCommits clearly to not shipping B and names mature results meeting thresholds as the condition for reconsideration.
  • Respects explicit constraintsAddresses Priya, leads with the recommendation, and stays within the 400-word limit.
  • Identifies material uncertaintyNames cohort maturity, refund denominator, refund reasons, plan mix, and the revenue CI as open questions and says mature, threshold-meeting results are required.
  • Avoids unsupported claimsCausal explanation is labelled plausible/not proven, and it does not present the mechanism as fact.
  • Produces the required deliverableProvides a complete, actionable recommendation and defense for Priya in the requested format.
  • Checks guardrails before declaring a winnerIt explicitly evaluates both the retention and refund guardrails before making the call.
  • Separates effect from explanationMechanism is labelled as a plausible explanation, not a proven finding.
  • Gets the base of every number rightAll derived differences and percentages (1.3pp, -4.5pp, +42%, $0.19) are computed from the correct bases.

Grades and run details

Decision model 90 · LLM judge 10 of 11 checks
Decision model checks
  • passUses the supplied evidence correctly27%
  • passAddresses the actual decision96%
  • passRespects explicit constraints40%
  • passIdentifies material uncertainty84%
  • partialAvoids unsupported claims23%
  • passProduces the required deliverable85%
  • passChecks guardrails before declaring a winner88%
  • passSeparates effect from explanation89%
  • partialTrusts the data before reading it27%
  • passGets the base of every number right83%
Run
Run
#1
API response time
14 s
Submitted
29 Sept 2026

Results

Every setup we’ve tested on this task, across all cases and repeats, graded on the current checklist. Calibrated: the graders match our PM on 88% of checks.

#Model · HarnessTask scoreDecision modelLLM judgeRunsCritical failures
1GPT-6 AstrawithChatGPT94.795.02None
2GPT-6 LunawithAPI89.490.52None
3GPT-6.1 SolwithAPI89.490.52None
4Sonnet 5.5withAPI81.775.92None
5Opus 5.5withClaude76.157.32None
6Gemini 3.5 Flash-LitewithGemini62.857.721 capped

About the task

The PM job

Reading a test readout and deciding what to do next.

Why it matters

Experiment readouts are where false confidence is cheapest to produce and most expensive to act on. A model that declares a winner on conversion while retention quietly falls will ship the wrong thing.

What good looks like

  • Checks the result can be trusted before interpreting it
  • Reports effects with their uncertainty
  • Checks guardrail metrics before declaring a winner
  • Separates what the data shows from plausible explanations
  • Recommends a next step proportionate to the evidence

Deliberately not measured

  • Re-running the statistics from raw data
  • Chart production
Capability tested

Interpreting results within their limits

The failure we’re looking for

Claims causality, ignores guardrails or recommends arbitrary testing

Grading

Decision model and LLM judge, calibrated against a blind PM review