# 坪田ラボ (4890.T) — per-stock model accuracy

> Model predictability decomposition: measures how accurately the ml-factor-lgbm-9f-jp-growth model family predicts this stock's returns within the jp-listed universe. High hit_rate_long does NOT mean 'good stock to buy' -- it means 'the model historically predicted this stock well when selecting it LONG'. This is a property of model-stock fit, not intrinsic stock quality.

- **Name**: 坪田ラボ
- **Sector**: 医薬品
- **Universe**: jp-listed
- **Decomposes**: `ml-factor-lgbm-9f-jp-growth` (strategy verdict: marginal) — https://qbuntu.ai/strategies/ml-factor-lgbm-9f-jp-growth
- **Computed asof**: 2026-10-01T02:33:09
- **HTML**: https://qbuntu.ai/stocks/4890.T
- **JSON**: https://qbuntu.ai/v1/stocks/4890.T
- **License**: CC-BY-4.0

## Accuracy (median across grid)

Median LONG hit rate is 0.4477 — below a coin flip.

| metric | median | p25 | p75 | n |
|---|---:|---:|---:|---:|
| hit_rate_long | 0.4477 | 0.3653 | 0.4779 | 12 |
| hit_rate_short | 0.6764 | 0.5073 | 0.7390 | 12 |
| avg_return_long_bps | -48.9 | -160.0 | -29.5 | 12 |
| avg_return_short_bps | 536.5 | 391.1 | 569.2 | 12 |
| selection_rate_long | 0.0079 | 0.0072 | 0.0089 | 12 |
| selection_rate_short | 0.0106 | 0.0098 | 0.0125 | 12 |

Hit rate ≈ 0.5 means the model's picks on this stock were near coin-flip. Returns in bps/trade. Metrics with n = 0 are omitted; n < 5 is a thin sample.

## PnL contribution

- long: -40.6
- short: 228.7
- total: 188.1
- appearances: LONG 3559 / SHORT 4698 of 422592

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Research, not investment advice. These metrics describe model–stock fit, not the stock's merit.
Cite as: qbuntu (2026). 4890.T per-stock accuracy. https://qbuntu.ai/stocks/4890.T