Initial README — Phase 7 ckpts on Gemma-2-2b base

README.md

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+---
+license: mit
+tags:
+  - sparse-autoencoder
+  - temporal-crosscoder
+  - gemma-2-2b
+---
+
+# txcdr-base — Temporal Crosscoder checkpoints (Phase 7, Gemma-2-2b base)
+
+This repo contains SAE / TXC / MLC / TFA checkpoints **trained on
+`google/gemma-2-2b` (base, NOT IT)** as part of Phase 7 of the
+Temporal Crosscoders project.
+
+All ckpts in this repo were trained at:
+
+- Subject model: `google/gemma-2-2b` (base).
+- Anchor layer: 0-indexed L12 (≈ 50% model depth) — matches T-SAE
+  (Ye et al. 2025) and TFA (Lubana et al. 2025).
+- Sparsity: `k_win = 500` global TopK on `d_sae = 18432` (with one
+  paper-faithful exception, `tsae_paper_k20`).
+- Probing protocol: long-tail sliding mean-pool, S = 128 tokens.
+
+## Related repositories
+
+| repo | purpose | model regime |
+|---|---|---|
+| [`han1823123123/txcdr`](https://huggingface.co/han1823123123/txcdr) | Phase 5 / 5B ckpts | **gemma-2-2b-IT** (historical) |
+| [`han1823123123/txcdr-data`](https://huggingface.co/datasets/han1823123123/txcdr-data) | Phase 5 / 5B caches | **gemma-2-2b-IT** (historical) |
+| **`han1823123123/txcdr-base`** (this repo) | **Phase 7 ckpts** | **gemma-2-2b base** |
+| [`han1823123123/txcdr-base-data`](https://huggingface.co/datasets/han1823123123/txcdr-base-data) | Phase 7 activation + probe caches | **gemma-2-2b base** |
+
+> **DO NOT MIX** ckpts from the IT and base repos. The residual
+> stream of `gemma-2-2b` and `gemma-2-2b-it` differ; Phase 7 ckpts
+> were trained on base activations and are not compatible with IT.
+
+See the project's `docs/han/research_logs/phase7_unification/`
+directory at https://github.com/chainik1125/temp_xc for the full
+Phase 7 plan.