Debates about whether development projects improve living conditions persist, partly because observational estimates can be biased by incomplete adjustment and because reliable outcome data are scarce at the neighborhood level. We address both issues in a continent-scale, sector-specific evaluation of Chinese and World Bank projects across 9,899 neighborhoods in 36 African countries (2002-2013), representative of ~88% of the population. First, we use a recent dataset that measures living conditions with a machine-learned wealth index derived from contemporaneous satellite imagery, yielding a consistent panel of 6.7 km square mosaics. Second, to strengthen identification, we proxy officials' map-based placement criteria using pre-treatment daytime satellite images and fuse these with tabular covariates to estimate funder- and sector-specific ATEs via inverse-probability weighting. Incorporating imagery often shrinks effects relative to tabular-only models. On average, both donors raise wealth, with larger and more consistent gains for China; sector extremes in our sample include Trade and Tourism (330) for the World Bank (+12.29 IWI points), and Emergency Response (700) for China (+15.15). Assignment-mechanism analyses also show World Bank placement is often more predictable from imagery alone (as well as from tabular covariates). This suggests that Chinese project placements are more driven by non-visible, political, or event-driven factors than World Bank placements. To probe residual concerns about selection on observables, we also estimate within-neighborhood (unit) fixed-effects models at a spatial resolution about 67 times finer than prior fixed-effects analyses, leveraging the computer-vision-imputed IWI panels; these deliver smaller but, for Chinese projects, directionally consistent effects.

翻译：关于发展项目能否改善生活条件的争论持续存在，部分原因是观测性估计可能因调整不完整而产生偏差，且社区层面的可靠结果数据较为匮乏。本研究针对这两个问题，在洲际尺度上对中国和世界银行项目进行了分部门评估，覆盖36个非洲国家（2002-2013年）的9,899个社区，代表约88%的非洲人口。首先，我们采用最新数据集，通过从同期卫星影像中提取的机器学习财富指数衡量生活条件，构建了由6.7平方公里网格组成的连续面板数据。其次，为强化因果识别，我们利用处理前的日间卫星影像模拟官员基于地图的选址标准，并将其与表格协变量融合，通过逆概率加权方法估计了资助方与部门特定的平均处理效应。引入影像数据后，效应值通常较纯表格模型有所收缩。平均而言，两家资助方均提升了财富水平，其中中国项目的效应更大且更稳定；样本中效应极端的部门包括世界银行的贸易与旅游业项目（330个，+12.29 IWI点）和中国的应急响应项目（700个，+15.15 IWI点）。选址机制分析还表明，仅凭影像数据（以及表格协变量）往往能更准确地预测世界银行项目的选址。这暗示中国项目的选址比世界银行项目更多受到不可见的政治或事件驱动因素影响。为探究可观测变量选择的残余问题，我们进一步利用计算机视觉推算的IWI面板数据，在空间分辨率比先前固定效应分析精细约67倍的尺度上估计了社区内固定效应模型；该模型得到的效应值较小，但对中国项目而言方向保持一致性。