HN mining: Jev vs chat LLMs on 400 Show HN comments
Binary classification (does a comment share a project?) over a stratified sample of 18,417 previously-processed Show HN comments. Every number below is from lab-measured runs through OpenRouter on 2026-09-20: typesafe/jev-1.13 decisions and four chat models under strict structured output.
What the data says
Quality: a statistical tie
All five models agree with each other 88-95% of the time, and JEV sits at the center of that consensus. No model is meaningfully "smarter" at deciding whether a comment shares a project - so quality cannot decide this comparison. Cost and speed can.
Cost: not close
400 classifications: JEV $0.009, cheapest chat model $0.048 (5x), frontier-sized Muse Spark $2.21 (238x). Across the full 18,417-row corpus: $0.43 with JEV, $2.20 with the cheapest chat model, $102 with Muse Spark.
Speed: not close
Median 0.35s per decision vs 1.1-12.8s. Full corpus, 8 workers: JEV ~14 minutes; the historical interactive LLM pass took 26 hours for the same rows and cost $3.14 - JEV is 7x cheaper and ~110x faster than it.
Confidence you can automate on
JEV's stated confidence tracks its real accuracy (93% correct when it says 95%+, 60% when unsure). That means: automate the confident 69%, send the uncertain 31% to a human or a pricier model. Chat models expose no comparable confidence.
Where JEV loses
It cannot write a single word - project names and pitches still need a generating LLM, so it complements extraction instead of replacing it. And on subjective 6-way tasks (exp2) its accuracy edge disappears; there you buy it for cost, speed, and determinism only.
Expensive ≠ better
Muse Spark, the largest and priciest model tested, had the lowest consensus agreement (93.5%) and the slowest answers (12.8s). Price bought size, not fit: a small decisions model matched or beat it on this workload.
Bottom line
For bulk classification, JEV delivers chat-model-quality decisions at 5-238x lower cost and 3-37x faster - with calibrated confidence that tells you which rows deserve human attention. Use it as the filter; keep an LLM for the rows it flags and for anything that needs writing.
How JEV does this
One call per comment. The comment is the state; two questions ride on it - a Choice with described labels and a Score with described levels (never numeric scales). The reply carries the decision, full probabilities, and a calibrated confidence:
Calibration explorer
JEV returns a confidence with every answer. Below: observed agreement with the prior pass, bucketed by stated confidence. Drag the threshold to see what a production filter would keep and how much it would cost.
Five models, one task
The 15% disagreement zone
All but one of JEV's disagreements with the prior pass are prior-pass-project → JEV-not-project. Spot checks show they cluster on "working on X" intent comments where the prior pass appears title-biased ("Show HN" ≠ shareable artifact). JEV's confidence marks the genuinely ambiguous ones - filter the sample below by disagreement and confidence.
Browse the sample
| id | sample | prior | JEV | conf |
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