| --- |
| language: |
| - en |
| license: apache-2.0 |
| library_name: transformers |
| pipeline_tag: text-generation |
| tags: |
| - math |
| - reasoning |
| - chain-of-thought |
| - qwen2 |
| - conversational |
| - rlvr |
| base_model: Qwen/Qwen2.5-0.5B-Instruct |
| --- |
| |
| # MathPhD++ 0.5B |
|
|
| **MathPhD++** is a small (≈0.5B parameter) language model fine-tuned for **mathematical reasoning** in natural language. It is built on [Qwen2.5-0.5B-Instruct](https://huggingface.co/Qwen/Qwen2.5-0.5B-Instruct) and trained with the **MathPhD++** open-source pipeline (see linked code repository in your Hub “Model sources” if you publish it): supervised fine-tuning (SFT) on curated math instruction data with structured `<thinking>` / `<answer>` (and related) tags, optional process reward modeling (PRM), and reinforcement learning from verifiable rewards (GRPO) using SymPy-backed correctness checks. |
|
|
| This Hub release is intended as a **reproducible checkpoint** for research and experimentation on math LLMs at the edge of what fits comfortably on a single consumer or Colab GPU. |
|
|
| ## Model summary |
|
|
| | Attribute | Value | |
| |-----------|--------| |
| | **Architecture** | Qwen2 (causal LM), ~0.5B parameters | |
| | **Precision** | FP16 (typical Hub export) | |
| | **Chat format** | ChatML (`<|im_start|>` / `<|im_end|>`) — prefer `tokenizer.apply_chat_template` when available | |
| | **Primary use** | Step-by-step math word problems, competition-style reasoning (informal proofs / chain-of-thought) | |
| | **Developed by** | Edmon (Edmon02) — community research project | |
| | **Finetuned from** | `Qwen/Qwen2.5-0.5B-Instruct` | |
|
|
| ## Training data (high level) |
|
|
| SFT mixes multiple public sources (non-exhaustive; see project config for exact caps): |
|
|
| - MetaMath-style QA |
| - Competition MATH (train) |
| - GSM8K (train) |
| - OpenMathInstruct-2 (subset) |
| - NuminaMath-CoT (subset) |
|
|
| Examples are formatted in **ChatML** with structured assistant outputs (reasoning blocks and final answers) to encourage verifiable extraction and consistent formatting for downstream RL. |
|
|
| ## Evaluation (reported from project notebook run) |
|
|
| Results below are **indicative** and used a **200-sample** cap per benchmark (`QUICK_TEST`-style eval). For publication-quality numbers, run full GSM8K test (1,319) and a standard MATH split with fixed protocol. |
|
|
| | Benchmark | Subset / protocol | Accuracy | |
| |-----------|-------------------|----------| |
| | GSM8K | 200 / test | **18.5%** (37/200) | |
| | MATH | 200 / MATH-500 | **6.0%** (12/200) | |
|
|
| These scores reflect the **SFT-loaded** policy evaluated after the pipeline fix that loads fine-tuned weights from checkpoint storage (not the raw base model). A 0.5B model remains **capacity-limited** on MATH; GSM8K is the more informative “did SFT help?” signal at this scale. |
|
|
| ## How to use |
|
|
| ### Transformers (generate) |
|
|
| ```python |
| from transformers import AutoModelForCausalLM, AutoTokenizer |
| import torch |
| |
| model_id = "Edmon02/mathphd-plus-plus-0.5b" |
| tokenizer = AutoTokenizer.from_pretrained(model_id, trust_remote_code=True) |
| model = AutoModelForCausalLM.from_pretrained( |
| model_id, |
| torch_dtype=torch.float16, |
| device_map="auto", |
| trust_remote_code=True, |
| ) |
| |
| problem = "What is the sum of the first 100 positive integers?" |
| prompt = ( |
| "<|im_start|>system\nYou are MathPhD++, an advanced mathematical reasoning assistant. " |
| "Show your complete reasoning step-by-step.<|im_end|>\n" |
| f"<|im_start|>user\n{problem}<|im_end|>\n" |
| "<|im_start|>assistant\n" |
| ) |
| inputs = tokenizer(prompt, return_tensors="pt").to(model.device) |
| outputs = model.generate( |
| **inputs, |
| max_new_tokens=512, |
| do_sample=False, |
| pad_token_id=tokenizer.pad_token_id, |
| ) |
| print(tokenizer.decode(outputs[0][inputs["input_ids"].shape[1]:], skip_special_tokens=True)) |
| ``` |
|
|
| Use **greedy or low temperature** for benchmarking; use sampling for exploratory interaction. |
|
|
| ## Limitations |
|
|
| - **Small model:** Will underperform larger instruction models on hard competition math and long proofs. |
| - **Informal reasoning:** Outputs are not formally verified unless you pair the model with an external proof checker or code execution sandbox. |
| - **Data contamination:** Public math benchmarks overlap train/eval sources; treat leaderboard-style claims with care unless you hold out data strictly. |
| - **Language:** Primarily English math text; mixed-language or non-math prompts are out of distribution. |
|
|
| ## Bias, safety, and responsible use |
|
|
| This model inherits behaviors and limitations of the base Qwen2.5 model and the fine-tuning corpora. It may produce confident but incorrect mathematics. **Do not** use as a sole authority for safety-critical, financial, medical, or legal reasoning. Prefer human review and independent verification. |
|
|
| ## Environmental note |
|
|
| If your Hub UI shows an unrelated arXiv paper (e.g. carbon footprint of ML), that is often an **automatic metadata artifact**. This model card is the authoritative description; consider removing incorrect `arxiv:` tags under model settings. |
|
|
| ## Links |
|
|
| - **Checkpoints / artifacts (author):** [Google Drive — mathphd_checkpoints](https://drive.google.com/drive/folders/14T6zF9B_Zh0JbKUW2nFEWz7QrYtW_r85?usp=sharing) (SFT, PRM, GRPO, eval exports — access as permitted by owner) |
| - **Base model:** [Qwen/Qwen2.5-0.5B-Instruct](https://huggingface.co/Qwen/Qwen2.5-0.5B-Instruct) |
|
|
| ## Citation |
|
|
| If you use this model, cite the base model and this Hub repository as appropriate: |
|
|
| ```bibtex |
| @misc{mathphd_plus_plus_05b, |
| title = {MathPhD++ 0.5B: Math Reasoning Model (Qwen2.5-0.5B-Instruct fine-tune)}, |
| author = {Edmon02}, |
| year = {2026}, |
| howpublished = {\url{https://huggingface.co/Edmon02/mathphd-plus-plus-0.5b}}, |
| } |
| ``` |
|
|
| --- |
|
|
| *Model card written for professional Hub documentation. Update the GitHub URL and evaluation table when you publish full-benchmark runs.* |