Research World Models
Language models as AI research world models

A world model
for AI research.

Can research taste be measured?

Research agents can propose far more experiments than anyone can afford to run. We give language models past experimental results and ask them to predict which new ideas are worth the compute.

Zijun Wang*, Zewen Liu*, Minhua Lin, Zhaotian Weng, Zhan Shi, Bing He, Yisi Sang, Dakuo Wang, Benoit Dumoulin, Wei Jin, Yuyin Zhou, Cihang Xie, Hanqing Lu · *equal contribution

The same 13 models, before and after 320 experiment records go into context. OLMo3-100M · 160 held-out queries · Figure 3. Download phone version ↓

Built on 2,653 real experiment records · 9 research environments · 171,862 H100 GPU-hours. Model weights stay fixed; experience is supplied in context.

01 · Method

Predict the result before spending the compute.

A Research World Model (RWM) reads a research environment, a concrete code or recipe change, and records of past experiments, then predicts how much that change will help. The top predictions get run for real, and their outcomes become new records.

Past recordsenvironment · intervention · measured gain — from this setup or another
Research World Modela fixed LLM; records go into its context
Rank candidatespredicted gain for each proposed change
Run the top picksreal training runs, fixed budget
↺ Measured outcomes become new records for the next round
02 · Experience vs. model choice

Experience changes the leaderboard.

Without experiment records0 / 13 above ┆ best without records, 0.621
More reasoning doesn't replace experience. The same backbone at LOW reasoning effort with records scores 0.892; its best effort setting without records scores 0.654.
Same weights. Nothing is trained here: the only change between the two conditions is 320 experiment records in the prompt.
Exact values for all 13 models
ModelNo records320 recordsΔRank

OLMo3-100M, 160 held-out queries, HIGH effort where supported (Figure 3). Ranks use unrounded values. Download JSON

03 · Transfer and decisions

Experience transfers — and changes what gets run.

The harder test: predict in a setup the model has never seen records from. Qwen3-153M got zero target records; the RWM used 244 records from OLMo3, Marin and Nanochat. Held-out interventions and their near-duplicates were removed from the source data.

No Qwen3 records, better Qwen3 decisions: with 244 source records, Regret@3 falls 78%, Spearman rises 0.74 to 0.82, NDCG@3 rises 0.77 to 0.91.
Prediction
0.628 → 0.729

Mean Spearman over 5 pretraining targets using only other environments’ records. With same-environment records: 0.506 → 0.774.

Selection
52–58% ↓

Reduction in Regret@3 when choosing 3 of 16 candidates: 58.2% with in-environment records, 52.2% cross-environment.

Multi-round
+15.8% · +11.6%

Final best gain after 8 rounds × 3 picks, starting from in-environment or cross-environment records (no records = 100).

Where it breaks: cross-environment records improved prediction on all five pretraining targets, but experiment selection on only four. On Marin, ranking got better while the picks did not.

Lower regret means less gain lost by missing the best candidate — not less compute. Tables 2–5 and Figure 2 in the paper.

04 · Data and paper

Nine research environments, real experiments.

See all 9 environments (2,653 records)
EnvironmentStage · outcomeRecords
OLMo3 100M in-envcross-envPretraining · bits per byte ↓480
OLMo3 190M cross-envPretraining · bits per byte ↓132
Marin 153M cross-envPretraining · bits per byte ↓132
Nanochat 149M cross-envPretraining · bits per byte ↓132
Qwen3 153M cross-envPretraining · bits per byte ↓132
E2D2 170M (diffusion LM) in-envPretraining · bits per byte ↓661
Math distillation, Qwen3-1.7B in-envPost-training · AIME24/25 avg@32 ↑280
Code RL, OLMo-3-7B in-envPost-training · LiveCodeBench ↑149
Inference optimization, Gemma-4-E4B-it / vLLM in-envInference · quality-constrained tokens/s ↑555

in-env: evaluated with records from the same environment. cross-env: target for transfer among the five autoregressive pretraining environments.

Every experiment does more than test an idea. It produces knowledge that can help choose the next one — even in another research environment.

Paper

Language Models as AI Research World Models

Wang*, Liu*, Lin, Weng, Shi, He, Sang, Wang, Dumoulin, Jin, Zhou, Xie, Lu · arXiv 2610.12235, 2026

@misc{wang2026languagemodelsairesearch,
  title={Language Models as AI Research World Models},
  author={Zijun Wang and Zewen Liu and Minhua Lin and Zhaotian Weng and Zhan Shi and Bing He and Yisi Sang and Dakuo Wang and Benoit Dumoulin and Wei Jin and Yuyin Zhou and Cihang Xie and Hanqing Lu},
  year={2026},
  eprint={2610.12235},
  archivePrefix={arXiv},
  primaryClass={cs.CL},
  url={https://arxiv.org/abs/2610.12235}
}