| --- |
| license: cc-by-nc-sa-4.0 |
| language: |
| - en |
| tags: |
| - gemma |
| - quantization |
| - qat |
| - benchmark |
| - reproducibility |
| - llm-governance |
| - routing |
| pretty_name: Gemma 4 Quantization-Regime Study (QAT Q4_0 vs PTQ Q4_K_M) |
| size_categories: |
| - n<1K |
| --- |
| |
| # Gemma 4 Quantization-Regime Study (QAT Q4_0 vs PTQ Q4_K_M) |
| |
| A same-day 2×2 study (quantization regime × released model pair) of |
| governed routing quality for Gemma 4 12B IT (dense; a clean same-base |
| pair) and a 26B-class MoE released pair on one RTX 5070 Ti, run under a |
| fixed, bit-identical governance stack via Ollama. |
| Companion/sequel to the *Gemma 4 MTP Quality–Throughput Study* (2026-08-09, |
| DOI 10.5281/zenodo.21860461). |
| |
| Author: Taiko Toeda, Independent Researcher |
| ORCID: https://orcid.org/0009-0001-7267-0201 |
| Version: 1.0.2 |
| DOI: [10.5281/zenodo.21903706](https://doi.org/10.5281/zenodo.21903706) (v1.0.2; concept DOI [10.5281/zenodo.21875512](https://doi.org/10.5281/zenodo.21875512) resolves to the latest) |
| |
| ## Result boundary |
| |
| Aggregate route correctness spanned 0.738–0.760 on Core-500 (N=500 rows = |
| 100 paraphrase stems × 5); no equivalence test was run, and one |
| cross-model contrast (12B-PTQ vs 26B-PTQ) is nominally significant |
| (p=0.035). The within-pair regime effects were individually marginal and |
| oppositely signed — QAT −0.012 on the dense 12B (McNemar p=0.070) and |
| +0.018 on the 26B released pair (p=0.078) — and the regime × pair |
| interaction, an exploratory single-run endpoint, was +0.030 with a |
| stem-clustered bootstrap 95% CI of [+0.010, +0.052] (task-iid CI |
| [+0.008, +0.052]), concentrated in the volatile-current task family |
| (crossed pattern). Cross-regime byte-identity of temperature-0 outputs |
| was only 23–32 %, against same-configuration Smoke-100 repeats of |
| 100/100 in all four cells (including the CPU-offloaded 26B-PTQ cell, |
| across run windows) and a 100/100 `num_ctx` byte-identity control. |
| Safety-critical failure rates were 0.000 in seven of eight runs, with a |
| single over-verification event (0.008) in 26B-PTQ Core-500. |
|
|
| These results apply only to the measured GPU, runtime (Ollama 0.30.6), |
| the released model artifacts named in `ENVIRONMENT.md`, one governance |
| stack, and routing/abstention-style tasks. The 26B released pair |
| confounds regime with a possible base revision (25.8B vs 25.2B), an |
| expert configuration unverifiable from runtime metadata, and a |
| CPU-offload compute path; only the 12B pair is a clean same-base, |
| all-GPU contrast. All inferential results are exploratory (no |
| preregistration, single run per cell, no multiplicity correction). See |
| `CLAIMS_MATRIX.md` before reusing any claim. |
|
|
| ## Public artifact boundary |
|
|
| This public package excludes verbatim task prompts, generated output text, |
| raw row-level request records, local paths, and the private internal |
| archive. It retains the paper, processed measurements, per-family and |
| paired statistics, environment and model digests, the deterministic |
| analysis script, and SHA-256 hashes that identify every excluded raw |
| artifact (`data/RAW_ARTIFACT_HASHES.sha256`). The evaluation harness is |
| public at `github.com/mobius-style/mmv` (`operate-fr-bench/`); the |
| OPERATE-FR suite items themselves are project-local and identified by hash |
| in `ENVIRONMENT.md`. |
|
|
| ## Layout |
|
|
| `PAPER.md` — full study. `EXECUTIVE_SUMMARY.md` — condensed findings. |
| `CLAIMS_MATRIX.md` — claim-by-claim evidence boundaries. |
| `REPRODUCE.md` — commands and artifact map. `ENVIRONMENT.md` — pinned |
| environment, model digests, suite hashes. `data/` — processed tables and |
| statistics. `analysis/` — deterministic analysis script (Apache-2.0). |
| Licensing: see `LICENSE.md` (split license). |
|
|
