Litmus

The benchmark

Does 70% actually mean 70%?

A prediction is only useful if it’s honest about its own uncertainty. We run the full auditor over a held-out labeled set and measure two things independently: can it tell replicated from failed (discrimination), and do its probabilities mean what they say (calibration). The numbers below are computed live from the harness, not asserted.

Real papers, real outcomes

Sanity-check floor on 24 externally-labeled papers (6 harder / contested), full pipeline, live

Graded separation

The clearest signal: mean Litmus likelihood climbs monotonically with real reproducibility.

Retracted for cause3%
Failed replication33%
Robust / replicated82%
1.00
ROC-AUC
no misclassifications on this curated set (n=24)
100%
Accuracy @ 50%
8 robust / 16 not
0.060
Brier
95% CI (0.03–0.09)
100%
Run-to-run stability
3 re-audited, same band
PaperClassLitmusCorrect
Wakefield et al. — MMR and autismRetracted for cause3%
LaCour & Green — canvassing and attitude changeRetracted for cause3%
Mehra et al. — hydroxychloroquine (Surgisphere)Retracted for cause3%
Mehra et al. — cardiovascular disease & COVID (Surgisphere)Retracted for cause3%
Obokata et al. — STAP cells (article)Retracted for cause3%
Obokata et al. — STAP cells (letter)Retracted for cause3%
Hwang et al. — patient-specific stem cellsRetracted for cause3%
Bem — feeling the future (precognition)Failed replication15%
Scholl et al. — STK33 / KRAS synthetic lethalityharderFailed replication20%
Carney, Cuddy & Yap — power posingFailed replication21%
Bargh, Chen & Burrows — elderly primingFailed replication33%
Vohs, Mead & Goode — the psychological consequences of moneyharderFailed replication39%
Baumeister et al. — ego depletionFailed replication40%
Schnall, Benton & Harvey — cleanliness and moral judgmentharderFailed replication41%
Zhong & Liljenquist — cleanliness / Macbeth effectFailed replication44%
Strack, Martin & Stepper — facial feedbackharderFailed replication44%
Lyashenko et al. — receptor-based relative sensingRobust / replicated62%
LeCun, Bengio & Hinton — deep learningRobust / replicated73%
Tversky & Kahneman — judgment under uncertainty (anchoring)harderRobust / replicated78%
Kahneman & Tversky — prospect theoryharderRobust / replicated84%
Takahashi & Yamanaka — induced pluripotent stem cellsRobust / replicated85%
Harris et al. — array programming with NumPyRobust / replicated86%
Jinek et al. — CRISPR-Cas9 programmable cleavageRobust / replicated93%
Abbott et al. (LIGO) — gravitational waves (GW150914)Robust / replicated93%

Every row is a live audit reproducible from its DOI. This is a sanity-check floor on clear-cut and harder/contested cases, not proof the engine is perfect on genuinely ambiguous papers; the AUC carries a wide confidence interval at this sample size and the honest next step is to widen the slice toward the full corpora. Retraction detection legitimately contributes on the retracted rows. Check mark threshold is 50%.

Calibration harness

Validating the calibration math at scale

The real slice above proves discrimination on real outcomes but is small. To validate the calibration machinery (isotonic fit, per-field curves, reliability, ECE) at statistical scale, we run a synthetic set whose per-field base rates are drawn from the published replication literature. It is a harness for the math, not a claim about real papers, and is clearly labeled as such.

0.82
ROC-AUC
replicated vs failed
0.80
PR-AUC
precision–recall
0.178
Brier score
from 0.196 raw
0.093
Calibration error (ECE)
from 0.144 raw

Calibration

Reliability diagram on held-out papers

000.250.250.50.50.750.7511perfect calibrationpredicted replication likelihoodobserved replication rate
CalibratedRaw (uncalibrated)Closer to the diagonal is better.

Raw model scores are over-confident (they sit off the diagonal). Fitting isotonic calibration on the labeled training split pulls them onto it, ECE drops from 0.144 to 0.093. Because isotonic is monotone, discrimination (AUC) is unchanged, calibration is a free win on top of it.

Ablation

Each component earns its place

0.50.60.70.80.90.73Intrinsic only0.78+Extrinsic0.80+Adjudication0.82+Adversarial verifyROC-AUC

Discrimination climbs as we add signals: deterministic checks alone, then retrieved literature, then adjudication, then adversarial verification. Each rung is calibrated on train and scored on the same held-out set, nothing is arbitrary.

Against the baselines

Discrimination (ROC-AUC)

Random0.50

no signal

Base-rate (predict field mean)0.50

calibrated but non-discriminating

Published ML replication predictors0.68

text/metadata models (Yang, Youyou, Uzzi et al.); documented to degrade out-of-sample

Litmus (full, calibrated)0.82

this run

Per-field calibration

Base rates differ by field, so we calibrate by field

FieldBase rateAUCECEn
cancer preclinical40%0.780.13465
social psychology39%0.850.07065
biomedical50%0.840.08465
economics61%0.850.13455

A single global calibration would lie: psychology replicates at ~39%, economics at ~61%. One curve per field keeps the probabilities honest everywhere.

Methodology & honesty

Two evals, kept separate on purpose. The real slice at the top runs the full production pipeline on real papers with externally-sourced outcomes (Retraction Watch, Registered Replication Reports, Nobel/Turing-recognized foundational work); it is the honest test of discrimination, and it is deliberately small. The synthetic harness here uses a labeled set of 500 papers (per-field base rates from the published replication literature), split 50/50; the calibrator is fit on train and every metric is computed on held-out test by the same code that powers the product. It validates the calibration math at scale, not real-paper performance. Next step: extend the real slice toward the full corpora (RP:CB, RP:P, DARPA SCORE) with the identical harness. The bar to beat: published ML replication predictors reach ~0.68 AUC and degrade out-of-sample.