# Model Card · B4 — What caused this event, from the operator's free-text note?

*Generated 2026-09-02 from `reports/` — do not edit by hand.*

## What this model answers

What caused this event, from the operator's free-text note?

## Caveats

- Descriptions mix English and Kannada, often within one entry. Character n-grams are used rather than word tokenisation.
- Per-language F1 is reported because a single macro-F1 could hide a model that works on the English majority and fails on Kannada.

## Results

Ranked by **Macro F1 ↑** (higher is better). Every family that ran is listed, including those that lost — the comparison is the deliverable. Figures come from a single chronological split, so there is no spread to report.

| Model | Family | Macro F1 ↑ | Accuracy ↑ | Macro F1 · en ↑ | Macro F1 · kn ↑ | Fit | Beats baseline |
|---|---|---:|---:|---:|---:|---:|---|
| `tfidf_char_logreg` | nlp | 0.4782 | 0.6555 | 0.4833 | 0.4717 | — | yes |
| `majority` | baseline | 0.0441 | — | — | — | — | *baseline* |

**Best learned family: `tfidf_char_logreg`** at 0.4782, 10.8x the strongest baseline (`majority` at 0.0441).

## Reproduction

```bash
make data && make ingest && make features
make train-b
```

Seed `42`. Splits are chronological, never random.