# Nigeria Maize Weather-Yield Dataset
Reproducible state-year dataset linking Nigerian maize yield observations with
seasonal agro-meteorological features derived from NASA POWER daily data.
## Dataset v1.0
- States: 37
- Years: 2020–2024
- Observations: 185
- Target: `Yield_MT_Ha`
- Weather source: NASA POWER
- QC status: PASS WITH DOCUMENTED WARNINGS
- Frozen SHA-256: `09ab62faed51d7f391595068587d33595f49058ae1687621925cf12408c2f97c`
## Repository purpose
This repository contains the data-engineering and provenance layer:
coordinates, season windows, extraction, feature engineering, QC history,
QC outputs, provenance metadata, and the frozen Dataset v1.0.
Modeling lives in the companion repository:
`nigeria-maize-weather-yield-model`.
## Final dataset
`data/processed/nigeria_maize_weather_yield_2020_2024_v1.0.csv`
Do not modify Dataset v1.0. Derived datasets belong in the modeling repository.
## Known warnings
- `Mean_Tmax_C` and `Mean_RH_pct` are highly correlated.
- Ekiti and Ondo retain an identical weather profile after raw-source audit;
this is documented as a spatial-resolution characteristic.
- 18 observations have `|Rainfall_Anomaly_Z_2000_2019| > 5` and are retained
for robustness/sensitivity analysis.
- The pre-repair raw archive was not preserved; yield preservation was
independently verified by QC v2.5.7.
## QC history
`v2.1 → v2.2 → v2.3 → v2.4 → v2.5 → v2.5.1 → v2.5.2 → v2.5.3 →
v2.5.4 → v2.5.5 → v2.5.6 → v2.5.7 → v2.6.1 → v2.6`
See `docs/qc_history.md`.