highways promote concentration of both output and population into regional prefectures, at the expense of other prefectures. Since there are more small prefectures than large, the average is negative.

## **2.3 The complementarities between road investments and electrification**

Investments in roads or electrifications alone may have limited or even adverse impacts in some contexts, for some locations, and for some groups. On the one hand, electricity can stimulate local production. However, the lack of reliable transport infrastructure will reduce the potential gains, especially in more isolated areas. Electrification alone mostly increases productivity in remote locations that have high transport costs and tend to remain shielded from import competition (Behrens et al., 2006). While some positive effects driven by local demand are predicted from, say, greater access to electricity, these electrified locations may miss out on other regions’ increased import demand for their newly electrified goods simply because they lack the transportation connection.

On the other hand, connecting isolated locations may increase import competition and have adverse impacts on local economic activities and jobs. Using the insight from a spatial quantitative model, Moneke (2020) shows that in partial equilibrium, as previously autarkic regions gain access to markets, the preexisting employment in the manufacturing sector suddenly competes with manufacturing-sector varieties from larger, more productive agglomerations. Unless the initial manufacturing-sector productivity is high, the sectoral-employment share of the manufacturing sector in the location newly connected by roads would be expected to fall. However, as productivity in previously isolated locations improves in the wake of new road connections, the roll-out of electrification can lead some manufacturing sectors to become profitable for exports, and to such a degree that the manufacturing employment share may actually rise. In the context of Ethiopia, reduced-form analysis by Moneke (2020) shows that road access alone causes manufacturing employment to drop largely in skilled activities, and, by contrast, causes service employment to increase, largely in informal, small-scale retail jobs.

The enabling effects of investment in infrastructure on job creation may depend on the interactions of investments. Whether ”big push,”combined investments deliver higher benefits than isolated investments of only roads or only electrification remains an open empirical question. One of the few attempts to examine the issue is the work in Ethiopia by Moneke (2020), who finds that only the interactions of infrastructure investments - not isolated investments - gave rise to large effects on economic development.

Thus, this paper aims to complement existing empirical studies and to fill a research gap, by looking at both the average and heterogeneous impacts of investment in infrastructure, and by examining the complementarity effects between two types of investments, roads and electricity.

# **3 Data**

To analyze the effects of infrastructure on employment in sub-Saharan Africa, we use two geo-referenced, household surveys: the Living Standards Measurement Study (LSMS) surveys conducted between 2005 and 2019, and the Demographic and Health Surveys (DHS) conducted between 2000 and 2018. Both surveys are merged with spatial information on roads and electricity grids.

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