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Revise README for adaptive LoRA findings and clarity

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Updated README to reflect key findings and improvements in adaptive LoRA fine-tuning with FSM-driven adapter switching. Enhanced clarity on performance under noisy training conditions and revised project description.

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  # Unified-LoRA
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- **An exploration of adaptive LoRA fine-tuning.**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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- This project investigated two ideas: (1) dynamically adjusting LoRA rank during training, and (2) using an FSM controller for training stability. Both were tested rigorously. Neither produced measurable benefit over simple baselines in multi-seed evaluation.
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- This repository documents the exploration honestly, including what worked, what didn't, and why.
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- ## What was built
 
 
 
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- Two systems:
 
 
 
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- **Adaptive Rank Controller** β€” each LoRA layer adjusts its rank during training based on gradient stress (EMA). Layers under stress get more capacity; stable layers get less.
 
 
 
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- **FSM Mode Controller Ο†(t)** β€” a finite state machine that monitors training loss, detects instability, and switches between operational modes (Normal β†’ Multi β†’ Mirror) with adaptive learning rate.
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- ## Results
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- ### Adaptive Rank β€” DistilBERT (67M), 3 GLUE tasks, 3 seeds
 
 
 
 
 
 
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- | Task | r=8 (fixed) | r=16 (fixed) | Adaptive | Avg Rank |
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- |------|-------------|--------------|----------|----------|
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- | MRPC (F1) | **0.885 Β± 0.007** | 0.882 Β± 0.006 | 0.862 Β± 0.025 | 9.1 |
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- | CoLA (MCC) | 0.474 Β± 0.001 | **0.478 Β± 0.011** | 0.477 Β± 0.021 | 7.0 |
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- | RTE (Acc) | **0.560 Β± 0.014** | 0.560 Β± 0.018 | 0.543 Β± 0.010 | 11.7 |
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- **Finding:** At this scale, r=8 β‰ˆ r=16. The rank choice doesn't matter, so the adaptive controller has no problem to solve.
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- ### Adaptive Rank β€” Qwen2.5-3B (3B, 4-bit), MRPC, 3 seeds, A100
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  | Mode | Acc | F1 | Rank |
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  |------|-----|-----|------|
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  | r=8 | 0.876 Β± 0.008 | 0.913 Β± 0.004 | 8 |
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  | r=16 | 0.875 Β± 0.004 | 0.913 Β± 0.002 | 16 |
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  | r=32 | 0.883 Β± 0.012 | 0.918 Β± 0.008 | 32 |
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- | Adaptive | 0.870 Β± 0.014 | 0.911 Β± 0.008 | 10.8 |
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-
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- **Finding:** Rank doesn't matter at 3B either. Gap between r=8 and r=32 is 0.5%.
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-
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- ### FSM Stability β€” Qwen2.5-3B + LoRA, MRPC, 3 seeds, A100
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- | Mode | F1 | F1 Std | Spikes |
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- |------|-----|--------|--------|
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- | Baseline (no protection) | **0.916 Β± 0.001** | | 330 |
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- | FSM Ο†(t) | 0.907 Β± 0.005 | | 306 |
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- | Cosine scheduler | 0.898 Β± 0.001 | | 335 |
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- **Finding:** Training instability (loss spikes) doesn't hurt final performance. The FSM reduces spikes slightly but at the cost of -0.9% F1 and higher variance.
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- ### FSM on Tinker β€” Llama-3.2-1B (single run, manually induced shock)
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  ```
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  [250] Mode=1 Ο†=0.333 (stable)
@@ -59,89 +95,42 @@ Two systems:
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  [700] Mode=1 Ο†=0.333 (baseline restored)
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  ```
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- **Finding:** The FSM mechanism works β€” it detects shock and recovers. But this was a single run with induced instability, not a multi-seed validation against alternatives.
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-
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- ## What was tested and didn't help
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-
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- Tested rigorously and documented honestly:
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-
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- - **Adaptive rank per-layer** (gradient EMA): rank adapts but doesn't improve results
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- - **Fluid dynamics metrics** (shock, vorticity, swirl): too conservative
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- - **Budget redistribution** across layers: winner-takes-all problem
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- - **Adaptive gradient clipping** via swirl: inconsistent
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- - **Vincolo integration** (StabilityController + rank): zero shock events on stable training
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- - **Predictive signals** (trend + acceleration): no improvement
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- - **FSM Ο†(t) on natural training**: either no instability to handle, or instability doesn't hurt results
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- - **Stress testing** (high LR + label noise): training collapsed before FSM could act
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-
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  ## What was learned
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- 1. **LoRA rank doesn't matter on classification tasks** from 67M to 3B. r=8 β‰ˆ r=16 β‰ˆ r=32 on MRPC. This means grid search over rank is wasted compute for these tasks.
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-
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- 2. **Training loss instability doesn't equal result instability.** Loss can spike wildly (0.0004 to 2.6) without affecting final metrics. Protecting against spikes is unnecessary on these tasks.
 
 
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- 3. **Simplest baseline wins.** Fixed rank, fixed LR, standard grad clipping outperformed every adaptive method tested.
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-
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- 4. **Single-seed results are misleading.** Several configurations showed positive results on single seeds that disappeared on multi-seed evaluation.
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- 5. **Per-layer rank patterns are real.** v_proj consistently needs more rank than q_proj, deep layers need more rank. These patterns reproduce across seeds even though they don't improve performance.
 
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- ## Per-layer behavior
 
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- The adaptive controller discovers consistent patterns:
 
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- ```
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- MRPC per-layer rank:
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- layer0.q: 7.9 layer0.v: 8.8
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- layer1.q: 7.8 layer1.v: 7.9
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- layer2.q: 7.9 layer2.v: 8.5
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- layer3.q: 8.8 layer3.v: 11.3 ← deep v_proj needs more
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- layer4.q: 10.3 layer4.v: 12.9
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- layer5.q: 7.6 layer5.v: 11.3
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  ```
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  ## Open questions
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- - Does rank matter on generation/instruction-following tasks (not classification)?
106
- - Does rank matter at 7B-70B scale with rank ranges of 8-64?
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- - Is there a training regime (specific LR + noise combination) where the FSM provides measurable benefit?
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-
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- ## Quick start
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-
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- ```python
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- from unified_lora import inject_lora, get_lora_modules, setup_trainable
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-
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- model = inject_lora(model, target_modules=["q_proj", "v_proj"])
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- model = setup_trainable(model)
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-
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- # In training loop:
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- for m in get_lora_modules(model):
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- m.update_rank() # adaptive rank (works mechanically, no performance benefit found)
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- ```
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-
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- ## Reproduce
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-
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- ```bash
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- pip install transformers datasets evaluate accelerate scikit-learn bitsandbytes
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-
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- # DistilBERT multi-seed validation (~20 min, T4)
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- python validation_complete.py
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-
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- # Qwen 3B scale test (~40 min, A100)
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- python scale_test.py
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-
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- # Qwen 3B stability test (~40 min, A100)
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- python stability_test.py
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- ```
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  ## Repository structure
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139
  ```
140
- unified_lora.py # Adaptive rank controller (drop-in module)
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- benchmark.py # DistilBERT single-run benchmark
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- validation_complete.py # Multi-seed + ablation (DistilBERT)
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- scale_test.py # Qwen 3B rank test (A100)
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- stability_test.py # FSM vs Baseline vs Cosine (A100)
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  controller.py # FSM Ο†(t) controller
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  Archive/ # Earlier experimental results
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  docs/ # Additional documentation
@@ -153,7 +142,7 @@ notebooks/ # Experiment notebooks
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  ```
154
  @software{unified_lora_2025,
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  author = {Simona Vargiu},
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- title = {Unified-LoRA: An Exploration of Adaptive LoRA Fine-tuning},
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  year = {2025},
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  url = {https://github.com/Sva76/Unified-LoRa}
159
  }
 
 
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  # Unified-LoRA
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+ **Adaptive LoRA fine-tuning with FSM-driven adapter switching.**
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+
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+ An exploration of adaptive LoRA fine-tuning that discovered a specific use case: under noisy training conditions, an FSM controller that switches between adapters of different rank based on training stress significantly outperforms fixed-rank LoRA.
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+
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+ ## Key finding
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+
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+ Under noisy conditions (label noise), the FSM adapter switching controller provides measurably better performance and lower variance than any fixed-rank baseline.
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+
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+ **5 seeds, DistilBERT + LoRA, MRPC, 50% label noise:**
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+
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+ | Method | Mean F1 | Std | Per-seed F1 |
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+ |--------|---------|-----|-------------|
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+ | r=4 fixed | 0.410 | 0.323 | [0.62, 0.61, 0.04, 0.01, 0.78] |
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+ | r=16 fixed | 0.439 | 0.234 | [0.73, 0.55, 0.31, 0.06, 0.55] |
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+ | **FSM switching** | **0.622** | **0.174** | [0.66, 0.29, 0.70, 0.65, 0.81] |
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+ | Random switching | 0.275 | 0.283 | [0.13, 0.08, 0.35, 0.01, 0.79] |
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+
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+ **Why this matters:**
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+ - FSM has the highest mean F1 (+18 points over best fixed rank)
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+ - FSM has the lowest variance (most robust across seeds)
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+ - Random switching is worst β€” proving the intelligence of the switching matters, not just having multiple adapters
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+ - Fixed ranks collapse on bad seeds (r4 β†’ 0.007, r16 β†’ 0.055); FSM never drops below 0.294
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+
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+ ## How it works
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+
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+ The FSM controller monitors training loss and switches between three LoRA adapters (r=4, r=8, r=16) based on a stress signal Ο†(t):
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+
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+ ```
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+ Ο†(t) = f(loss_EMA, instability, progress)
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+
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+ Ο† < ΞΈβ‚€ β†’ Mode 0: use r=4 adapter (low stress, light capacity)
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+ Ο† < θ₁ β†’ Mode 1: use r=8 adapter (moderate stress)
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+ Ο† β‰₯ θ₁ β†’ Mode 2: use r=16 adapter (high stress, full capacity)
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+ ```
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+ Under normal training, the controller stays in low-rank mode (efficient). When noise or instability hits, it switches to higher rank (resilient). When stress passes, it returns to low rank.
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+ ## Where it works and where it doesn't
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+ ### Works: noisy/unstable training
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+ - Label noise, data corruption, adversarial batches
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+ - The controller acts as a resilience mechanism
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+ - Degrades less than fixed rank under stress
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+ ### Doesn't work: clean training
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+ - On standard GLUE tasks without noise, r=8 β‰ˆ r=16 β‰ˆ r=32
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+ - The rank choice doesn't matter, so the controller has no problem to solve
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+ - Tested on DistilBERT (67M), TinyLlama (1.1B), Qwen2.5-3B β€” same conclusion
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+ ### Doesn't work: rank adaptation without switching
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+ - Per-layer gradient EMA rank controller was tested extensively
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+ - Multi-seed validation showed no benefit over fixed rank on clean data
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+ - Higher variance than fixed-rank baselines
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+ ## Full experimental history
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+ This project tested many approaches. In the interest of scientific honesty:
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+ **Tested and didn't help on clean data:**
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+ - Adaptive rank per-layer (gradient EMA) β€” no performance benefit
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+ - Fluid dynamics metrics (shock, vorticity, swirl) β€” too conservative
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+ - Budget redistribution across layers β€” winner-takes-all problem
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+ - Adaptive gradient clipping β€” inconsistent
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+ - Vincolo StabilityController integration β€” zero shock events on stable training
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+ - FSM with LR control only (no adapter switching) β€” loses to cosine scheduler
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+ **What works:**
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+ - FSM with adapter switching under noisy conditions (this finding)
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+ - FSM stress-recovery cycle validated on Tinker with Llama-3.2-1B
 
 
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+ ## Scale test results (clean data)
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+ Qwen2.5-3B, 4-bit, MRPC, 3 seeds, A100:
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  | Mode | Acc | F1 | Rank |
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  |------|-----|-----|------|
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  | r=8 | 0.876 Β± 0.008 | 0.913 Β± 0.004 | 8 |
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  | r=16 | 0.875 Β± 0.004 | 0.913 Β± 0.002 | 16 |
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  | r=32 | 0.883 Β± 0.012 | 0.918 Β± 0.008 | 32 |
 
 
 
 
 
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+ Rank doesn't matter at 3B on classification. Gap r=8 vs r=32: 0.5%.
 
 
 
 
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+ ## FSM on Tinker (Llama-3.2-1B)
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+ Demonstrated full stress β†’ recovery cycle with manually induced shock:
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  ```
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  [250] Mode=1 Ο†=0.333 (stable)
 
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  [700] Mode=1 Ο†=0.333 (baseline restored)
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  ```
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  ## What was learned
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+ 1. **LoRA rank doesn't matter on clean classification tasks** from 67M to 3B
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+ 2. **Under noise, adaptive switching beats fixed rank** β€” the FSM provides resilience
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+ 3. **Switching intelligence matters** β€” random switching is worst
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+ 4. **Single-seed results are misleading** β€” always use multi-seed
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+ 5. **The simplest baseline wins on clean data** β€” complexity only pays under stress
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+ ## Reproduce
 
 
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+ ```bash
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+ pip install transformers datasets evaluate accelerate scikit-learn peft
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+ # Clean data benchmark
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+ python benchmark.py
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+ # Multi-seed validation
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+ python validation_complete.py
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+ # Noisy training FSM test (the key finding)
118
+ python fsm_noise_test.py
 
 
 
 
 
 
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  ```
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  ## Open questions
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+ - Does FSM adapter switching help at 7B+ scale under noise?
124
+ - What noise levels trigger the benefit? (tested at 50%, untested at 5-20%)
125
+ - Does it help on generation/instruction tasks with naturally noisy data?
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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  ## Repository structure
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  ```
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+ unified_lora.py # Adaptive rank controller module
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+ benchmark.py # Clean data benchmark
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+ validation_complete.py # Multi-seed clean data validation
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+ fsm_noise_test.py # FSM adapter switching under noise (key result)
 
134
  controller.py # FSM Ο†(t) controller
135
  Archive/ # Earlier experimental results
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  docs/ # Additional documentation
 
142
  ```
143
  @software{unified_lora_2025,
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  author = {Simona Vargiu},
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+ title = {Unified-LoRA: Adaptive LoRA Fine-tuning with FSM Adapter Switching},
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  year = {2025},
147
  url = {https://github.com/Sva76/Unified-LoRa}
148
  }