---
base_model: vera6/affine-5g4yy75zuz-t6
base_model_revision: 8e3f1695e058837ed80fec3238ff439fdc2d0f0e
library_name: transformers
pipeline_tag: text-generation
license: apache-2.0
tags:
  - affine
  - sn120
  - reason-v4
  - offline-dpo
  - r861
---

# R861 — SoftCtx × MidRank × MidBeta UltraLoLR (offline DPO on vera king)

Affine SN120 challenger for **Reason v4** (`weight_version_key=7`): tempered
multi-sample log-mean-exp over k=3 teacher refs (τ=0.03).

Per turn: `a_i = lpC(y_i|z_A) − lpC(y_i|∅)`;
`Reason = τ·log(mean_i exp(a_i/τ))`. Crown also needs median stripped `|z|≥80`
and B pass ≥0.30.

## How this checkpoint was trained

- **Base / parent:** `vera6/affine-5g4yy75zuz-t6@8e3f1695e058837ed80fec3238ff439fdc2d0f0e` (live king reign36)
- **Method:** offline DPO on Reason-ranked duel pairs (not SFT / not online GRPO)
- **What was optimized:** preference for thoughts that raise teacher-side Reason
  (commit to a teacher next-action mode; filler loses under LME)
- **Data:** Soft Mid Mid Soft × SoftCtx filtered duel preference pairs from
  `dpo_duel_reason.jsonl` under `mining/experiments/r861-vera-offline-dpo-hialpha-midrank-midbeta-softctx-megasuperextrasteps-ep4-ultralolr` / pod `/root/r861/` (~259–604 rows at launch)
- **Key hyperparameters:**
  - LoRA r=**32** (MidRank), α=**128** (HiAlpha)
  - β=**0.1** (MidBeta)
  - lr=**5e-7** (UltraLoLR)
  - max_len=**12288** (SoftCtx)
  - max_steps=**19200** (MegaSuperExtra)
  - epochs=**4**
- **Hardware:** Lium `mine-crown-1` (gentle-orbit-bd) 8×B200 GPUs **4,5**
  train+merge+challenger serve + v4 n80 → `/tmp/r861_merged`
  (~66G / 16 safetensor shards; `weight_identical=false`)
- **Local n80 vs live king reign36** (`vera6/affine-5g4yy75zuz-t6@8e3f1695e058837ed80fec3238ff439fdc2d0f0e`) under **wvk=7**:
  - margin **+0.003665**, SE **0.001684**, z=**2.177**, n=**80**
  - bar `max(2·SE, δ=0.002)` = **0.003367** (~**1.088×**)
  - thought median **141.5** (≥80 ✓), B pass **0.5375** (≥0.30 ✓)
  - k=**3**, τ=**0.03** (fail-closed if stamp ≠ v4)
  - decision: **WIN / Stage-5 licensed** (`r861_decision_reign36_wvk7.json`, p3966)
- **Lineage:** R846 vera MidRank HiBeta SoftCtx REFUTE ~−0.33× → MidBeta isolate;
  ≠ R846 Hiβ / ≠ R847 HiRank Midβ SoftCtx / ≠ Online / ≠ GRPO
- **Experiment path:** `mining/experiments/r861-vera-offline-dpo-hialpha-midrank-midbeta-softctx-megasuperextrasteps-ep4-ultralolr`

## Intended use

SN120 Affine miner submission / evalsrv Reason v4 duel. Not a general chat model.

## License

Follows base model + Affine mining artifacts policy.