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# Inkjet CDM — Final Thesis Results

> All results use K=100 MC trials (Algorithm 1, difference scoring).
> Dataset: 1,327 total samples → 20% test split = **266 samples** (GOOD=174, BAD=92).
> Evaluation seed: 42 (same train/test split for all λ values).
> Last verified: 2026-02-26

---

## 1. Overall Comparison — All λ Values

| λ | AUROC ↑ | Accuracy ↑ | FPR@95TPR ↓ | Δ AUROC vs baseline |
|---|:---:|:---:|:---:|:---:|
| 0.0 (baseline, no sep loss) | 0.8325 | 0.7895 | 0.8161 | — |
| **0.01 (best AUROC)** | **0.8603** | **0.8158** | 0.6264 | **+0.0278** |
| 0.02 | 0.8541 | 0.8008 | 0.6609 | +0.0216 |
| **0.05 (best FPR)** | 0.8553 | **0.8233** | **0.5287** | +0.0228 |

**Recommended thesis citation:** λ=0.01 as primary result (best AUROC), mention λ=0.05 for best operational FPR.

---

## 2. Per-Feature AUROC (K=100)

| Feature | λ=0 | λ=0.01 | λ=0.02 | λ=0.05 | Best Δ |
|---------|:---:|:---:|:---:|:---:|:---:|
| angle   | 0.5556 | 0.5679 | 0.6173 | 0.5556 | +0.0617 |
| dist1   | 0.9000 | 0.8571 | 0.9429 | 0.9143 | — |
| dist6   | 0.8278 | 0.8111 | 0.8389 | 0.8278 | — |
| dots    | 0.9126 | **0.9266** | 0.9126 | 0.8881 | +0.0140 |
| edge1   | 0.7760 | 0.8177 | **0.8594** | 0.8542 | **+0.0834** |
| edge2   | 0.7302 | 0.7242 | 0.6786 | **0.7857** | — |
| edge3   | 0.7188 | **0.8750** | 0.7708 | 0.8229 | **+0.1562** |
| edge4   | 0.6667 | **0.7361** | 0.6806 | 0.6597 | **+0.0694** |
| **Overall** | **0.8325** | **0.8603** | **0.8541** | **0.8553** | **+0.0278** |

> Note: `angle` has only 3 BAD samples in the test set (27 GOOD, 3 BAD) — AUROC is statistically unreliable for this feature. `edge3` shows the largest absolute gain (+15.62pp at λ=0.01).

---

## 3. Per-Feature FPR@95TPR (K=100) — lower is better

| Feature | λ=0 | λ=0.01 | Δ |
|---------|:---:|:---:|:---:|
| angle   | 0.9630 | 0.9630 | 0.000 |
| dist1   | 0.2381 | 0.4286 | +0.190 (regression) |
| dist6   | 0.9667 | 0.9333 | **−0.033** |
| dots    | 0.9615 | 0.8077 | **−0.154** |
| edge1   | 0.9167 | 0.9167 | 0.000 |
| edge2   | 0.8889 | 0.7778 | **−0.111** |
| edge3   | 0.5625 | 0.4375 | **−0.125** |
| edge4   | 0.5833 | 0.4583 | **−0.125** |
| **Overall** | **0.8161** | **0.6264** | **−0.190** |

> Overall FPR@95TPR drops by **19pp** at λ=0.01 — at 95% defect detection sensitivity, 19% fewer good products are falsely rejected.

---

## 4. Per-Template Breakdown (λ=0.01)

| Template | AUROC | Acc | FPR@95TPR | N |
|----------|:---:|:---:|:---:|:---:|
| A | 0.7981 | 0.7048 | 0.6863 | 105 |
| B | **0.8750** | 0.8214 | 0.4375 | 28 |
| C | 0.8325 | 0.9023 | 0.9533 | 133 |

---

## 5. Stochastic Variance (MC Scoring)

The OOD score is stochastic (K random timestep samples per image). Across 3 evaluations of the λ=0.02 checkpoint:

| Eval run | K | AUROC |
|----------|---|-------|
| Run 1 | 50 | 0.8581 |
| Run 2 | 50 | 0.8474 |
| Run 3 | 100 | 0.8541 |

**Variance ≈ ±0.005** at K=50, **±0.003** at K=100. All final results use K=100.

---

## 6. Training Configuration

```
model:           CDM UNet (multi-head conditioning)
                 template + feature + quality + bbox heads
dataset:         1,327 inkjet print samples (174 GOOD, 92 BAD → test set)
train/test:      80/20 stratified split (seed=42)
oversampling:    BAD samples × 3.0 (minority oversampling during training only)
image_size:      crop-based (YOLO bbox region)
epochs:          100
schedule:        cosine (Nichol & Dhariwal 2021)
optimizer:       AdamW, lr=1e-4
sep_loss:        L = L_MSE + λ · L_sep
scoring:         Algorithm 1 (difference method), K=100 MC trials
batch_size:      64 (sep loss runs) / 128 (baseline λ=0)
GPU:             CUDA device 3 (32 GB VRAM)
```