r/MachineLearning post (copy-paste)

Title: [P] STRATA-Bench: a 36-task benchmark for whether AI agents know what a number is

Body:

TL;DR: New open-source benchmark (Apache-2.0) scoring whether AI agents can compile longitudinal market intelligence from fragmented, geographically nested, temporally incomplete evidence — without relabeling metro figures as downtown, silently interpolating missing quarters, or plotting gaps as data.

Motivation: A 2026 audit asked six frontier engines for a five-year downtown condo rent series from public sources. They split into three archetypes: Empirical Literalists (faithful to the board, honest about geography), Synthetic Econometricians (modeled a downtown premium, disclosed it), and Fragmented Extractors (OCR’d charts, skipped 9/20 quarters, plotted gaps as equal ticks). This benchmark turns that failure mode into a scored protocol.

What’s in it:

  • 36 sandbox tasks + 3 live probes across 6 failure families: GEO (geographic masking), TEMP (temporal attrition), SRC (source blending/OCR), INT (silent interpolation), AXIS (non-uniform axes), SYN (synthetic blending)
  • Self-contained synthetic corpus (fictional Meridian Metro board, consultancy, listing site, adversarial traps) — no external data needed
  • Scoring: disclose / tag / refuse / model — hard fails (geographic masking, silent interpolation, paywall fabrication) cap a task at 55% of earned credit
  • 3 reference agents shipped as regression fixtures

Try it: pip install strata-bench, then strata-bench evaluate submissions/examples/extractor.json --format text — watch the reference extractor get caught.

New in v1.1.0: community leaderboard — PR your agent’s run under submissions/community/ and a bot auto-scores it and posts a scorecard.

Repo: github.com/movahedi-ca/strata-bench · Docs: movahedi-ca.github.io/strata-bench

Happy to answer questions about the failure taxonomy and scoring protocol.