Skills are a central source of high productivity and economic well-being. But what do we mean by productive skills? Both with regard to measurement and policy, the primary focus in the U.S. has been on academic skills, as measured by tests of reading, writing and math abilities and by...

Time plays an important role in both the design and interpretation of evaluation studies of training programs. While the start and duration of a training program are closely linked to the evolution of job opportunities, the impact of training programs in the short and longer term changes over...