One Model Family, Two Gold-Level Results: Fine-Tuning Nemotron for IOI and IMO
https://huggingface.co/blog/nvidia/nemotron-ioi-and-imo-2026📌 【NVIDIA 最新研究】Nemotron 同時拿下 IOI 與 IMO 2026 金牌門檻
TL;DR:NVIDIA 用同一套 Nemotron 3 基礎模型,分別微調出在 IOI 2026 與 IMO 2026 都達金牌水準的專家系統。
競程與數學奧賽考驗完全不同的能力:IOI 要求程式碼在嚴格時間與提交限制下通過隱藏測試,IMO 則要求嚴謹的自然語言證明。NVIDIA 的 Nemotron 團隊用同一個模型家族,在兩場比賽都做到金牌等級,這指向一個更大的命題——基礎模型的可微調性,可能比單一領域的表現更值得關注。
🤔 核心問題:一個基礎模型能否可重複地變成多個領域專家
NVIDIA 想驗證的是:Nemotron 3 是否是一個足夠強、足夠「好微調」的基礎模型,能用一套可重複使用的流程,分別打造出競程與數學證明兩個完全不同領域的世界級專家系統。
🧩 一套四步驟的通用特化配方
團隊總結出的流程分四步:
- 從一個強大的 Nemotron 基礎模型出發。
- 整理領域專屬的題目,並產生高品質的推理軌跡(reasoning traces)。
- 套用標準的後訓練方法,包括 SFT(監督式微調),必要時加上 RL(強化學習)。
- 將專家模型搭配一套能生成、評估並改進候選答案的推論迴圈。
競程方向:團隊整理了 22,000 道題目並產生合成推理軌跡,訓練出兩個專家模型——30B 總參數/3B 活躍參數的 Nemotron-3-Nano-CC(接受 SFT 與 RL),以及 550B 總參數/55B 活躍參數的 Nemotron-3-Ultra-CC(僅接受 SFT)。團隊也開發了 GenCorrect,一種反覆生成、評估、修正的測試時(test-time)策略。
數學證明方向:以 Nemotron 3 Ultra 為起點,訓練一個 SFT 專家與一個 RL 專家。SFT 訓練資料包含 414,890 筆經品質篩選的樣本,涵蓋 15,818 道獨特證明題,內容不只是最終答案,還包括證明生成、修正、驗證與元驗證(meta-verification),讓模型學會建構論證、找出漏洞、回應質疑並判斷證明是否完整。RL 模型則在 9,597 道、貼近模型能力邊界的證明題上訓練。最終系統讓兩個專家模型與通用模型一起針對每道 IMO 題目生成候選證明、評分、產出評語並修正最有潛力的嘗試,再由一個獨立的高運算量階段挑選最終提交版本。整套系統全程使用自然語言,沒有使用形式化證明器、外部工具或網路存取。
📊 從一般能力到金牌分數的進展
IOI 2025 上的進展清楚展示了特化的價值:
| 階段 | Nano 分數 |
|---|---|
| 後訓練前 | 130 |
| SFT 後 | 280 |
| +RL 後 | 291 |
| +GenCorrect | 468(金牌門檻 438.3) |
Ultra-CC 搭配同樣的測試時策略達到 502 分。
| 比賽 | 特化方式 | 結果 |
|---|---|---|
| IOI 2026 | Nemotron-3-Ultra-CC,SFT+GenCorrect | 535.4/600,高於金牌門檻 361.12,也高於人類最高分 498.27 |
| IMO 2026 | Nemotron 3 Ultra 通用模型+SFT/RL checkpoint 組成的生成-驗證-修正系統 | 30/42,高於官方金牌門檻 29,六題中四題拿到滿分 |
IOI 的結果來自一次即時、前瞻性的測試,遵循與人類選手相同的時間、網路存取與提交限制,但屬於非官方、未受監督的基準測試,未列入官方排名。IMO 的證明則由官方 IMO 評審評分。
💡 SFT 與 RL 的分工不是固定公式
兩個專案都顯示,適配方式不必在每個規模上都長得一樣。在競程方向,Nano 的進步主要來自 SFT,RL 帶來的提升較小但穩定;而對更強的 Ultra 模型,只需一個 SFT epoch 就能超越完整後訓練過的 Nano,在 IOI、ICPC、LiveCodeBench Pro 上皆是如此。在數學證明方向,SFT checkpoint 在第一輪搜尋中表現最強,RL checkpoint 則拿下整體最佳的單一 checkpoint 成績,兩者優勢互補,因此最終系統同時保留了兩個專家模型與通用模型。團隊強調,這些金牌成績不是單靠微調,也不是單靠暴力取樣得來,而是模型、資料與推論迴圈共同設計的結果。
⚠️ 局限
IOI 2026 的成績屬於非官方、未受監督的基準測試,並未計入正式排名;IMO 系統完全依賴自然語言推理,沒有形式化證明器或外部工具輔助,兩者都是在特定條件下取得的結果,與正式比賽規則仍有差異。
🎯 實務啟示
NVIDIA 公開了完整的可重現資源:Nemotron Labs IMO 2026 collection(SFT/RL checkpoint、兩份訓練資料集,以及新發布的 200 題 Nemotron-IMO-Bench)、記錄訓練方法與系統設計的 IMO 論文,以及包含推論管線、提示詞與已提交證明的 NeMo-Skills репозиторий(含可重現的 quickstart)。競程方面,Nemotron-3-Ultra-CC 模型與 IOI 論文、GenCorrect 方法論,以及對應的評測與推論管線同樣開放於 Hugging Face 與 NeMo-Skills。對於想把通用基礎模型微調成特定領域專家的團隊,這套「基礎模型+資料策展+後訓練+生成驗證迴圈」的配方具有高度參考價值。
🔗 來源
- 標題:One Model Family, Two Gold-Level Results: Fine-Tuning Nemotron for IOI and IMO
- 作者/機構:NVIDIA(Aleksander Ficek、Igor Gitman、Sean Narenthiran、Mehrzad Samadi、Somshubra Majumdar)
- 連結:https://huggingface.co/blog/nvidia/nemotron-ioi-and-imo-2026
#NVIDIA #Nemotron #LLM #ReinforcementLearning #SFT #IMO #IOI #AIResearch #MachineLearning #OpenSource
原始資料 HuggingFace Blog · 收集於 2026-10-07
摘要原文
Back to Articles One Model Family, Two Gold-Level Results: Fine-Tuning Nemotron for IOI and IMO Enterprise + Article Published October 7, 2026 Upvote 8 +2 Aleksander aficek Follow nvidia Igor Gitman igitman Follow nvidia Sean Narenthiran SeanNaren Follow nvidia Mehrzad Samadi mehrzads Follow nvidia Somshubra Majumdar smajumdar94 Follow nvidia The International Olympiad in Informatics (IOI) and the International Mathematical Olympiad (IMO) test different skills. IOI requires algorithms and code that pass hidden tests under strict time and submission limits. IMO demands rigorous natural-language proofs. Success at either competition is difficult. Success at both points to something broader. Our recent results show that Nemotron is a strong, adaptable foundation for building world-class specialist models. Starting from Nemotron 3, our teams used supervised fine-tuning (SFT), reinforcement learning (RL), and feedback-driven inference to create systems that reached gold-medal level at both IMO 2026 and IOI 2026 . Competition Nemotron specialization Result IOI 2026 Nemotron-3-Ultra-CC with SFT and GenCorrect 535.4/600, above the 361.12 gold threshold and the top human score of 498.27 IMO 2026 Nemotron 3 Ultra general, SFT, and RL checkpoints in a generate-verify-refine system 30/42, above the official gold threshold of 29 The IOI result came from a live, prospective run under the same time, internet-access, and submission constraints as human contestants. It was an unofficial, unsupervised benchmark and was not included in the official IOI ranking. The IMO system’s submitted proofs were graded by official IMO graders. A reusable specialization recipe "Easy to fine-tune" should mean more than making a checkpoint trainable. It should mean that a capable foundation model can be adapted to a demanding domain with a clear, reusable recipe. Across the two projects, that recipe had four parts: Start with a strong Nemotron base model. Curate domain-specific problems and high-quality reasoning traces. Apply standard post-training methods such as SFT and, where useful, RL. Pair the specialist model with an inference loop that generates, evaluates, and improves candidate answers. The training and inference runs were substantial, but the underlying approach is familiar and reproducible. We did not need to build a new foundation model for every challenge. We specialized Nemotron for the task. From general coding ability to IOI gold For competitive programming, we curated 22,000 problems and generated synthetic reasoning traces to train two specialists. Nemotron-3-Nano-CC, with 30 billion total parameters and 3 billion active parameters, received both SFT and RL. Nemotron-3-Ultra-CC, with 550 billion total parameters and 55 billion active parameters, received SFT. The progression on IOI 2025 makes the value of specialization easy to see. Nano improved from 130 points before post-training to 280 after SFT and 291 after RL. With GenCorrect, our iterative generate-evaluate-refine strategy, it reached 468 points and crossed the gold threshold of 438.3. Ultra-CC reached 502 points with the same test-time strategy. These experiments also showed that adaptation does not have to look the same at every scale. SFT produced most of Nano's gain, with RL adding a smaller but consistent improvement. For the stronger Ultra model, one SFT epoch was enough to outperform the fully post-trained Nano model across IOI, ICPC, and LiveCodeBench Pro. That finding guided the competition-specific Ultra-CC system used for IOI 2026, which scored 535.4 out of 600. Teaching Nemotron to prove, check, and revise The IMO project applied the same idea to olympiad mathematics. Starting from Nemotron 3 Ultra, we trained one specialist with SFT and another with RL. The SFT corpus contained 414,890 quality-filtered examples across 15,818 unique proof problems. It did more than teach final answers. The data covered proof generation, refinement, verification, and meta-verification, so the model learned to construct arguments, identify gaps, respond to critiques, and judge whether a proof was complete. The RL model was trained on 9,597 proof problems selected near the model's capability frontier. Both post-trained checkpoints outperformed the general-availability model in the development experiments. The SFT checkpoint was strongest in the first search round, while the RL checkpoint achieved the best overall single-checkpoint result. Their strengths were complementary, so the final system used both specialists alongside the general model. For each IMO problem, the models generated candidate proofs, scored them, produced critiques, and refined the most promising attempts. A separate high-compute stage selected the final submission. The entire system worked in natural language, with no formal prover, external tools, or internet access. It scored 30 out of 42 points, including full credit on four of the six problems, and exceeded the official gold-medal threshold. Fine-tuning and test-time compute work together Our earlier IOI 2025 Hugging Face post showed how test-time compute can push open-weight models to gold-level performance. The new results add an important piece: better specialization gives the inference system better candidates, better critics, and better refinements. At IOI, GenCorrect turned the gains from fine-tuning into larger improvements over multiple feedback rounds. At IMO, using complementary SFT and RL checkpoints was more valuable than simply drawing more samples from one checkpoint. In both cases, the best outcome came from combining a capable specialist with a system that could search, verify, and improve. This distinction matters. The medals were not produced by fine-tuning alone, and they were not produced by brute-force sampling alone. They came from co-designing the model, the data, and the inference loop. Open models, data, and recipes on Hugging Face We want these results to be useful beyond the competitions. The Nemotron Labs IMO 2026 collection brings together the SFT and RL checkpoints, both training datasets, and Nemotron-IMO-Bench, a new benchmark of 200 olympiad-level problems. The IMO paper describes the training approach and generate-verify-refine system, while the NeMo-Skills repository includes the IMO inference pipeline, prompts, submitted proofs, and a reproducible quickstart. For competitive programming, the Nemotron-3-Ultra-CC model is available on Hugging Face, and the IOI paper provides the training recipe and the GenCorrect methodology. The IOI evaluation and inference pipeline are also available in NeMo-Skills . Together, IMO and IOI provide unusually demanding evidence for a simple idea: Nemotron can be fine-tuned into world-class domain specialists, then composed with transparent inference workflows to solve problems at the frontier of human competition. We are excited to see what the Hugging Face community builds next.
由 claude-code/sonnet 自動生成