README.md
| 1 | --- |
| 2 | license: apache-2.0 |
| 3 | pipeline_tag: tabular-classification |
| 4 | tags: |
| 5 | - arxiv:2609.04540 |
| 6 | --- |
| 7 | |
| 8 | # Mitra-v2 Classifier |
| 9 | |
| 10 | Mitra-v2 classifier is a tabular foundation model that is pre-trained on purely synthetic datasets sampled from a mix of random classifiers, including the new Hybrid SCM prior. It is the second generation of the Mitra classifier ([autogluon/mitra-classifier](https://huggingface.co/autogluon/mitra-classifier)), pre-trained with a 10x longer context, three times as many features, and an improved optimizer. On the TabArena and TALENT benchmarks it delivers state-of-the-art accuracy at the level of TabFM and EXAONE Tabular, while surpassing TabPFN-3 by a wide margin. The regression model is at [autogluon/mitra-regressor-2](https://huggingface.co/autogluon/mitra-regressor-2), and the inference and fine-tuning code with our evaluation results is at [autogluon/mitra-finetune](https://huggingface.co/autogluon/mitra-finetune). |
| 11 | |
| 12 | ## Architecture |
| 13 | |
| 14 | Mitra-v2 is based on a 12-layer 2D Transformer of 75.7 M parameters (attention across rows and across columns), pre-trained by incorporating an in-context learning paradigm. The architecture is unchanged from Mitra-v1; the gains come from the scaled-up synthetic pre-training distribution and the optimizer. |
| 15 | |
| 16 | ## Usage |
| 17 | |
| 18 | To use Mitra-v2 classifier, install AutoGluon and the `mitra-finetune` package by running: |
| 19 | |
| 20 | ```sh |
| 21 | pip install uv |
| 22 | uv pip install "autogluon.tabular[mitra]>=1.6" "tabarena>=0.1.0" |
| 23 | uv pip install git+https://huggingface.co/autogluon/mitra-finetune |
| 24 | ``` |
| 25 | |
| 26 | A minimal example showing how to fine-tune and predict with the Mitra-v2 classifier using the same recipe as our reported results (50-step fine-tuning with 8-fold bagging). The recipe fine-tunes and bags eight copies of the model and requires a CUDA GPU; each `predict_proba` or `predict` call runs one bagged fine-tune: |
| 27 | |
| 28 | ```python |
| 29 | import pandas as pd |
| 30 | from sklearn.model_selection import train_test_split |
| 31 | from sklearn.datasets import load_wine |
| 32 | from huggingface_hub import snapshot_download |
| 33 | from mitra_finetune import MitraFinetune |
| 34 | |
| 35 | # Load dataset |
| 36 | wine_data = load_wine() |
| 37 | X = pd.DataFrame(wine_data.data, columns=wine_data.feature_names) |
| 38 | y = pd.Series(wine_data.target, name="target") |
| 39 | X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=42, stratify=y) |
| 40 | |
| 41 | # Download the Mitra-v2 classifier weights |
| 42 | ckpt_dir = snapshot_download("autogluon/mitra-classifier-2") |
| 43 | |
| 44 | # Fine-tune and predict |
| 45 | model = MitraFinetune(checkpoint_dir=ckpt_dir, problem_type="classification") |
| 46 | model.fit(X_train, y_train) |
| 47 | proba = model.predict_proba(X_test) |
| 48 | pred = proba.argmax(axis=1) |
| 49 | print("Accuracy:", (pred == y_test.values).mean()) |
| 50 | ``` |
| 51 | |
| 52 | A minimal example showing how to perform inference with the Mitra-v2 classifier directly in AutoGluon (the weights are a drop-in replacement for the Mitra-v1 classifier): |
| 53 | |
| 54 | ```python |
| 55 | from autogluon.tabular import TabularDataset, TabularPredictor |
| 56 | |
| 57 | train_data = TabularDataset(pd.concat([X_train, y_train], axis=1)) |
| 58 | test_data = TabularDataset(pd.concat([X_test, y_test], axis=1)) |
| 59 | |
| 60 | mitra_predictor = TabularPredictor(label="target") |
| 61 | mitra_predictor.fit( |
| 62 | train_data, |
| 63 | hyperparameters={ |
| 64 | "MITRA": {"hf_model": "autogluon/mitra-classifier-2", "fine_tune": False} |
| 65 | }, |
| 66 | ) |
| 67 | |
| 68 | mitra_predictor.leaderboard(test_data) |
| 69 | ``` |
| 70 | |
| 71 | Set `"fine_tune": True` to fine-tune inside AutoGluon. Note that AutoGluon's stock defaults differ from the `mitra-finetune` recipe used for the reported benchmark numbers. |
| 72 | |
| 73 | ## License |
| 74 | |
| 75 | This project is licensed under the Apache-2.0 License. |
| 76 | |
| 77 | ## Reference |
| 78 | |
| 79 | [Mitra-v2 Technical Report](https://arxiv.org/abs/2609.04540) (Amazon, 2026), also available on the [Hub](https://huggingface.co/autogluon/mitra-finetune/blob/main/Mitra_v2_Technical_Report.pdf). |
| 80 | |
| 81 | ``` |
| 82 | @article{mitrav2_2026, |
| 83 | title={{Mitra-v2} Technical Report}, |
| 84 | author={Tao, Yefan and Zhang, Xiyuan and Liu, Xinyi and Han, Boran and Maddix, Danielle and Fang, Haoyang and Han, Zhen and Gai, Jiading and Liu, Xuanqing and Bohlke-Schneider, Michael and Wang, Yuyang (Bernie) and Friedland, Gerald and Mah, Kevan and Lee, Chris and Kong, Chris}, |
| 85 | journal={arXiv preprint arXiv:2609.04540}, |
| 86 | year={2026} |
| 87 | } |
| 88 | ``` |
| 89 | |
| 90 | The original Mitra: |
| 91 | |
| 92 | ``` |
| 93 | @article{zhang2025mitra, |
| 94 | title={Mitra: Mixed synthetic priors for enhancing tabular foundation models}, |
| 95 | author={Zhang, Xiyuan and Maddix, Danielle C and Yin, Junming and Erickson, Nick and Ansari, Abdul Fatir and Han, Boran and Zhang, Shuai and Akoglu, Leman and Faloutsos, Christos and Mahoney, Michael W and others}, |
| 96 | journal={arXiv preprint arXiv:2510.21204}, |
| 97 | year={2025} |
| 98 | } |
| 99 | ``` |
| 100 | |
| 101 | Amazon Science blog: [Mitra: Mixed synthetic priors for enhancing tabular foundation models](https://www.amazon.science/blog/mitra-mixed-synthetic-priors-for-enhancing-tabular-foundation-models) |
| 102 | |