Open multimodal benchmark for measuring and modeling intra-urban deprivation across sub-Saharan African cities using public spatial data, weak supervision, and external validation.
SSA Urban Deprivation Benchmark
Transfer evaluation of public-data deprivation proxies across sub-Saharan African cities.
## Research Question
When a target city has no local survey labels, can public spatial data provide a useful and transferable deprivation proxy? The project compares an interpretable infrastructure-scarcity atlas with spatial interpolation, gradient boosting, convolutional models, multimodal fusion, and a spatial graph model.
The central comparison is deliberately conservative: a complex model is useful only when it improves on both the atlas and a coordinates-only spatial interpolation baseline under a transfer protocol that prevents local spatial leakage.
## Study Design
| Component | Primary benchmark | Transfer extension |
| --- | --- | --- |
| Cities | 7 cities | 14 cities in 7 countries |
| Grid | 500 m cells | 500 m cells |
| Benchmark support | 15,030 rows in GHS-SMOD classes 21, 22, 23, and 30 | 23,273 rows in GHS-SMOD classes 21, 22, 23, and 30 |
| Main protocol | 8-seed leave-one-city-out | Leave-one-city-out, leave-one-country-out, and same-country transfer |
| Evaluation unit | Primary RWI support cluster | Primary RWI support cluster |
The core7 cities are Accra, Addis Ababa, Dar es Salaam, eThekwini, Kampala, Nairobi, and Port Harcourt. The core14 extension adds Dire Dawa, Enugu North, Jinja, Johannesburg, Mombasa, Mwanza-Nyamagana, and Tamale.
The weak target is the negative raw Relative Wealth Index (RWI). RWI is relative within country and is not an absolute cross-country wealth scale. Regression targets are standardized within each training fold; classification is defined as the lowest 20% of reliable RWI values within each city. Metrics are aggregated by primary RWI support rather than treating interpolated 500 m cells as independent survey observations.
## Results
### Core7: Eight-seed LOCO
Values are unweighted means of city-level support-cluster metrics across eight seeds. RMSE is lower-is-better; Sp …