What it is
Scores Jev (TypeSafe System One) on 5,000 real CDC BRFSS 2015 respondents against logistic regression, a hand-written rule, a chat LLM, and the base rate. For researchers evaluating decision models.
How it uses Jev
Jev reads plain-English survey answers and judges heart-disease risk. It returns typed output with a checkable reason. The result is used as a ranking score, not a calibrated probability; the cut-off is set in code.
Primitives:choice
Technique worth stealing
Use Jev for selection among plausible options, not calibrated probability of a rare event.
Try it
Open the interactive demo: https://rubinagentagi-tech.github.io/jev-heart-risk-bench/
Evidence
Each line is one question put to Jev about the README. ≥ 0.60 reads as yes, ≤ 0.40 as no; in between Jev is not making a call.
- Jev-centricyes0.83
- Shows a System One patternno0.25
- Handles uncertaintyno0.05
- Measuredno0.26
- Runnableno0.11
- Worth recommendingunclear0.42
- Model replicano0.04
- Problem scopescore on a 0–2 scale0.26
- About Jevyes0.98
Signals by Jev jev-1.13.0, card written by DeepSeek V4.1 Flash from the README on 20 Sept 2026.