Of the major kinds of physical infrastructure, electricity generating capacity has roughly the same marginal productivity as physical capital as a whole. So have roads-plus-rail, globally and in lower-income countries. Telephones, however, and transport routes in higher-income countries, have...

Large potential benefits of infrastructure may elude identification and measurement by conventional cost-benefit analysis. Canning and Bennathan estimate social rates of return on general capital, by examining the effect on aggregate output and comparing that effect with the costs of construction

Of the major kinds of physical infrastructure, electricity generating capacity has roughly the same marginal productivity as physical capital as a whole. So have roads-plus-rail, globally and in lower-income countries. Telephones, however, and transport routes in higher-income countries, have...