# TF-IDF vs Voyage vs Cohere — 3-Way Comparison

## Retrieval Accuracy (top-1 matches expected)

| Language | TF-IDF | Voyage | Cohere | Best |
|----------|--------|--------|--------|------|
| French | 72% (18/25) | 100% (25/25) | 96% (24/25) | Voyage |
| MSA | 8% (2/25) | 96% (24/25) | 100% (25/25) | Cohere |
| Derja (Arabic) | 8% (2/25) | 72% (18/25) | 84% (21/25) | Cohere |
| Derja (Arabizi) | 24% (6/25) | 36% (9/25) | 24% (6/25) | Voyage |

## Score Distribution (expected chunk)

| Language | Method | Mean Score |
|----------|--------|------------|
| French | TF-IDF | 0.5288 |
| French | Voyage | 0.7287 |
| French | Cohere | 0.5672 |
| MSA | TF-IDF | 0.0078 |
| MSA | Voyage | 0.5629 |
| MSA | Cohere | 0.4267 |
| Derja (Arabic) | TF-IDF | 0.0051 |
| Derja (Arabic) | Voyage | 0.4240 |
| Derja (Arabic) | Cohere | 0.3222 |
| Derja (Arabizi) | TF-IDF | 0.0801 |
| Derja (Arabizi) | Voyage | 0.3626 |
| Derja (Arabizi) | Cohere | 0.1728 |

## False Negative Rate

TF-IDF: score < 0.001 | Voyage/Cohere: score < 0.7

| Language | TF-IDF FN | Voyage FN | Cohere FN |
|----------|-----------|-----------|----------|
| French | 0% (0/25) | 20% (5/25) | 100% (25/25) |
| MSA | 92% (23/25) | 96% (24/25) | 100% (25/25) |
| Derja (Arabic) | 96% (24/25) | 100% (25/25) | 100% (25/25) |
| Derja (Arabizi) | 64% (16/25) | 100% (25/25) | 100% (25/25) |

## Arabizi vs Arabic Script

| Variant | TF-IDF | Voyage | Cohere |
|---------|--------|--------|--------|
| Derja (Arabic) | 8% | 72% | 84% |
| Derja (Arabizi) | 24% | 36% | 24% |

## Recommendation

**Use the method with the best multilingual performance.**

All three methods were tested on the same 25-chunk French KB with 145 queries.