Analyst Bench · Pilot-1 · Error patterns

Finding a data problem is not the same as respecting it

Across 72 answers from four AI analyst agents, the serious errors were rarely bad arithmetic. They were conclusions that went past the evidence: the right analysis of the wrong population, a causal effect claimed from an experiment the agent had just called invalid, a customer's motive invented from a payment log, a budget forecast read off historical averages.

Completing the judge panel changes the error labels more than the ordering

The case map and taxonomy counts below retain the original r4 panel. A separate post-results check adds 54 blind reviews: all 72 answers now have GPT, Claude and Grok judges. Shared-panel means are 99.60, 83.73, 81.82 and 83.00 for Codex, Claude Code, Grok Build and Antigravity, respectively; core successes are 14/14, 10/14, 9/14 and 7/14.

Silent errors are 0/18, 5/18, 6/18 and 14/18. The same answers receive different labels when evaluator composition and warning interpretation change. Five statements retain exact three-way splits, and equal assignment does not prove unbiased grading or zero true errors. Read the before/after report.

All 72 answers

Passed, no wrong claim Passed, with a wrong claim Failed Dot: a wrong claim had no specific warning

One cell per answer, labelled by run (1 or 2). Amber cells are the ones a score alone would wave through. Use “Show on map” on any pattern below to highlight the answers it describes.

Error labels by product

answers of 18

Answers with at least one claim carrying each taxonomy label, as assigned by the cross-vendor judges. Labels overlap, so rows do not add up.

Where passing answers go wrong

Each bar is one product's 18 answers. Amber is the share a pass/fail score would miss.

The evaluator made pattern 1 too

Before the r4 correction, the automatic matcher compared numbers with the right shape but the wrong identity: an account median against a mean, active users against all assigned users, a later small purchase against the original refunded payment. Correct supplementary numbers were marked as errors. The audit found this, fixed it, and regraded all 72 answers. A matching number only means something after the population, statistic, event and time window match.

What a human reviewer should check

Running these tasks yourself

The tasks, results and these error cases are public, so an agent with web access could find what each task tests. Turn off web search and URL fetching for the agent, and ideally allow network access only to the model's own inference endpoint, as the Pilot-1 harness did. If a product's server-side search cannot be switched off, record and report every search it makes. Treat any new scores as a fresh run on known tasks, not as a continuation of Pilot-1.

Limitations