Checkpoint
Table | |
|---|
| Role | Student after on-policy distillation with forward KL |
| What it is | On-policy distillation for 42 steps from the Qwen3-4B trailing-text teacher (ErrOPD-Qwen3-4B-teacher-SQL), starting from the Qwen3-1.7B SQL student (ErrOPD-Qwen3-1.7B-student-SQL); objective: forward KL (cross-entropy on one teacher sample at each student prefix); seed 6001. |
| Paper reference | Table 2 (SQL trailing text, forward KL) |
| Task | Spider 1.0 text-to-SQL: given a SQLite schema and a question, output one SQL query on a single line and nothing else |
| Training data | distillation prompts opd_prompts.jsonl of XINLI1997/ErrOPD-Spider (1,795, disjoint from the fine-tuning pool); the student generates on them and the teacher gives per-token targets on the student's prefixes |
| Base model | Qwen/Qwen3-1.7B |
| Seed | 6001 |
| Weights | bf16 safetensors, 1 file, 4.06 GB (2.03 B stored parameters). The file also stores lm_head.weight, a bit-identical copy of the tied input embeddings. |
Usage
# pip install "transformers>=4.57.0" accelerate datasets torchimport torchfrom datasets import load_datasetfrom transformers import AutoModelForCausalLM, AutoTokenizer repo = "XINLI1997/ErrOPD-Qwen3-1.7B-SQL-fKL"tokenizer = AutoTokenizer.from_pretrained(repo)model = AutoModelForCausalLM.from_pretrained(repo, dtype=torch.bfloat16, device_map="auto") # one held-out prompt (system + user turns) from the evaluation splitexample = load_dataset("XINLI1997/ErrOPD-Spider", split="validation")[0]messages = [m for m in example["messages"] if m["role"] != "assistant"] inputs = tokenizer.apply_chat_template(messages, add_generation_prompt=True, return_tensors="pt", return_dict=True).to(model.device)output = model.generate(**inputs, max_new_tokens=512, do_sample=False)print(tokenizer.decode(output[0, inputs["input_ids"].shape[1]:], skip_special_tokens=True))
The expected output is one SQLite query on a single line (run it against the Spider database named in metadata.db_id to check it). Prompts, decoding settings and the scoring code used in the paper are in the code repository.
Notes:
- The bundled chat template is the one used for fine-tuning, distillation rollouts and evaluation in the paper.
Training
On-policy distillation for 42 steps from the Qwen3-4B trailing-text teacher (ErrOPD-Qwen3-4B-teacher-SQL), starting from the Qwen3-1.7B SQL student (ErrOPD-Qwen3-1.7B-student-SQL); objective: forward KL (cross-entropy on one teacher sample at each student prefix); seed 6001. Full training configurations and scripts are in the code repository.
Evaluation
This checkpoint is reported in the paper, Table 2 (SQL trailing text, forward KL); see that table for its scores.
Limitations
- Trained for one narrow structured-output task. It is not a general assistant, and outputs for other prompts are not meaningful.
- Teachers in this release were fine-tuned to make an injected format error on purpose; distilled students may inherit it. This is what the paper measures.
- Evaluated on a 500-question subset of Spider dev; generated SQL should be executed in a sandbox.
License
Apache-2.0, inherited from the base model Qwen/Qwen3-1.7B (see LICENSE). The training data keep their own terms (see the dataset card of XINLI1997/ErrOPD-Spider).
Citation
@article{li2026erropd, title = {ErrOPD: When Does On-Policy Distillation Transfer Teacher Errors?}, author = {Li, Xin and Jiang, Hao and Wang, Annan and Zhang, Yichi and Yuen, Chau}, journal = {arXiv preprint arXiv:2605.08737}, year = {2026}}