README.md

---
language:
- en
license: other
license_name: pd-seeds-deterministic-rejected
license_link: https://www.gutenberg.org/policy/permission.html
task_categories:
- text-generation
tags:
- dpo
- orpo
- preference
- prose
- writing-style
- single-axis
size_categories:
- n<1K
---

# Kadenz-DPO

*German "Kadenz": cadence.*

**596 pairs teaching one lesson — vary your sentence length.**

`chosen` is unedited human prose from US-public-domain novels. `rejected` is the *same passage*
with its rhythm regularised: long periods split at coordinators and semicolons, short adjacent
sentences fused, every sentence pushed toward the mean length. Nothing else changes. No model
touched either side.

| field | content |
|---|---|
| `prompt` | a continuation instruction plus the first 60 words of the passage |
| `chosen` | the passage's actual continuation, human-written, untouched |
| `rejected` | the same continuation, rhythm-flattened |
| `delta` | how much `sent_len_cv` dropped from `chosen` to `rejected` |
| `edits` | number of split/fuse operations applied |

## Why this axis

Measured against a human reference distribution built from
[`schneewolflabs/fundgrube`](https://huggingface.co/datasets/schneewolflabs/fundgrube)
(1,483 passages, 8 style features), every instruct model tested writes with markedly *less*
sentence-length variation than human novelists — one of the two largest deviations from human
prose, alongside repetitive sentence openers:

| | sent_len_cv | z vs human |
|---|---|---|
| human (fundgrube) | 0.74 | — |
| Qwen3.6-27B (instruct) | 0.55 | −1.1 |
| Qwen3.6-27B-TIES | 0.46 | −1.7 |
| Fable-Fusion-711-27B | 0.51 | −1.4 |

Humans mix four-word sentences with forty-word ones. These models write metronomically. The
degradation applied here (`sent_len_cv` −0.209 mean) is deliberately sized to span that gap, so
the preference signal covers the distance between human prose and real model output rather than
a subtler distinction the model would never encounter.

## Construction

Deterministic, no LLM in the loop — the same method as
[`schneewolflabs/hecke-dpo`](https://huggingface.co/datasets/schneewolflabs/hecke-dpo),
which injects hedges into the same corpus.

1. 320-word passages drawn from `fundgrube` chapters.
2. Passages with >25% dialogue sentences are skipped — quoted speech has its own rhythm and
   re-bounding across quotation marks produces ungrammatical splices.
3. Long sentences (>1.6× the passage mean) are split at `;` and coordinating conjunctions;
   adjacent short sentences (<0.5× mean) are fused with ", and".
4. **Content preservation is enforced, not assumed.** Every pair is checked so that `rejected`
   contains the same words as `chosen` modulo connectives (≤2% word-multiset difference).
   An earlier version dropped short fragments during splitting, which truncated clauses — that
   would have taught "prefer the complete text" rather than "prefer varied rhythm". Pairs failing
   the check, or containing punctuation artifacts, are discarded.
5. Pairs where the transform failed to degrade `sent_len_cv` by >0.02 are discarded.

Verification stats over the released set:

| | value |
|---|---|
| pairs | 596 |
| `sent_len_cv` degradation | mean 0.209, median 0.182, max 1.108 |
| split/fuse edits per passage | 4.5 |
| words per side | 260 (identical between chosen and rejected by construction) |

## Example

**chosen**
> …sought for her there had been wakened that wonderful vision to which alone are wonderful
> things revealed; the mere shapes and patterns of things becoming, as it were, refined, and
> gaining a kind of symbolical value…

**rejected**
> …for her there had been wakened that wonderful vision to which alone are wonderful things
> revealed. The mere shapes and patterns of things becoming, as it were, refined. …

## Limitations

- **Archaic `chosen` side.** The source is pre-1930 public-domain fiction, so training on it
  nudges diction toward period style as a side effect of teaching rhythm. Stacking this with
  other fundgrube-derived sets (e.g. `hecke-dpo`) compounds that drift. Mixing in modern
  permissively-licensed prose on the `chosen` side would isolate the axis more cleanly.
- **Some `rejected` sentences are fragments.** Splitting at a coordinator occasionally yields a
  clause without a finite verb. That is a second, unintended defect riding along with the
  intended one; a POS-aware splitter would avoid it.
- **Narration only.** Dialogue-heavy passages are excluded, so the axis is untrained for dialogue
  rhythm.
- **Not decontaminated** against any benchmark.

## Related

- [`schneewolflabs/fundgrube`](https://huggingface.co/datasets/schneewolflabs/fundgrube) — the human source corpus
- [`schneewolflabs/hecke-dpo`](https://huggingface.co/datasets/schneewolflabs/hecke-dpo) — same method, hedging axis
- **Auftakt-DPO** (planned) — the companion axis: sentence-opener monotony