facilitate the travel of administration officials and military troops from the capital city to other regions of the country, and the movement of people and goods between different ethnic homelands. Leveraging this premise for our analysis, we construct hypothetical roads linking ancestral ethnic homelands from the capital of each country to instrument for the actual road network. We use a least-cost algorithm, assuming that land altitude is the main geographic determinant of construction costs for roads. The exclusion restriction is likely to be met because these hypothetical roads are conditional only on geographic costs of construction, not demand-side factors. Moreover, the set of ethnic groups and homelands in each country is exogenously determined, given the arbitrary partition of Africa.

Estimates suggest positive and significant employment effects of proximity to roads, proximity to electricity grids, and the interaction of the two. For people in locations sufficiently close to an electric grid, bringing the main road 10 km closer increases the probability of being employed by between 2.5 percentage points (based on the LSMS sample) and 26 percentage points (based on the DHS sample). Greater road access also increases the number of hours worked by 1.2 hours per week (DHS sample). For locations sufficiently close to a main road, bringing an electric grid 10 km closer increases the likelihood of being employed by between 6 percentage points (LSMS sample) and 8.4 percentage points (DHS sample). Greater proximity to an electric grid also raises the number of hours worked by 12.5 hours per week (DHS sample).

Our estimates also reveal complementarity. We show that bringing an electricity grid closer to a location increases the positive marginal impact of bringing a main road closer; and, in turn, bringing a main road closer to a location increases the positive marginal impact of bringing an electric grid closer. Specifically, we find that bringing an electric grid 10 km closer increases the probability of working by more than 8.4 percentage points in locations that have direct road access, but by only 4 percentage points in locations that are more than 10 km away from a main road (DHS sample). Similarly, bringing the main road network 10 km closer increases the probability of working by more than 25 percentage points when that location is near an electric grid, but by only 21 percentage points when it is located more than 10 km away from an electric grid. The results suggest that road and electricity expansions play complementary roles in job creation.

We also show that infrastructure investments impact the structure of employment and that they spur structural transformation at the local level. That is, better access to road and electricity networks increases employment in skilled occupations, and decreases employment in unskilled occupations, especially self-employment in agriculture. Roads and electricity again play complementary roles. Together, they raise the probability of being employed with a skilled job and decrease the probability of having an unskilled job.

Taking advantage of the fine granularity of the available data, we analyze the heterogeneous effects of infrastructure investments between more-developed and less-developed countries, between rural and urban areas, and across gender and age groups. We find that expanding access to roads and electricity, both separately and jointly, has a greater positive impact on employment in more-developed African countries than in countries that are less developed. Our comparison of rural and urban locations shows that greater proximity to a main road has a greater effect on rural households, increasing skilled employment and reducing unskilled employment. We find that the employment gains due to infrastructure 3