README.md

---
license: apache-2.0
task_categories:
  - text-generation
tags:
  - forge-3b
  - dpo
  - preference-pairs
  - direct-preference-optimization
---

# FORGE-3B DPO Preference Data

Tokenized (prompt, chosen, rejected) preference triples for DPO post-training
of FORGE-3B, built per the FORGE paper Section 6.2 / Appendix A.2.

**This is data preparation output only — no model was trained to produce this.**

## Stats
- **Total pairs**: 0 (paper target: ~200,000)
- **Domains**: 0/4
- **Context length**: 4096 tokens (paper Appendix A.2, DPO block)
- **Format**: unpacked — one (prompt, chosen, rejected) triple per training example
- **Chat template**: `<|SYS|>...<|/SYS|>` `<|USR|>...<|/USR|>` `<|ASST|>...<|/ASST|>` (identical to SFT)
- **Tokenizer**: CRAYON (xerv-crayon) ONLY — no fallback tokenizer is used, since
  DPO requires exact token-id alignment with the frozen SFT reference model
  (paper Sec 6.2)

## Domain Breakdown

| Domain | Pairs | Sources |
|:-------|------:|:--------|
| ultrafeedback | — | ✗ |
| helpsteer2 | — | ✗ |
| hh_rlhf_helpful | — | ✗ |
| hh_rlhf_harmless | — | ✗ |

## Usage

```python
import numpy as np
from huggingface_hub import hf_hub_download

path = hf_hub_download(
    repo_id="Phase-Technologies/forge-3b-dpo-data",
    filename="ultrafeedback/train_shard_0000.npz",
    repo_type="dataset",
)
data = np.load(path, allow_pickle=True)
chosen_full_ids = data["chosen_full_ids"]      # object array of int32 arrays
rejected_full_ids = data["rejected_full_ids"]   # object array of int32 arrays
chosen_loss_mask = data["chosen_loss_mask"]     # 1 = completion token (compute logprob here)
rejected_loss_mask = data["rejected_loss_mask"]
```

## Per FORGE paper Section 6.2 DPO config
- β = 0.1
- lr = 5e-7 (constant)
- batch = 32 preference pairs/step
- grad_clip = 0.3
- reference_model = frozen SFT checkpoint