During times of major technological change leading cities are often overtaken by upstart metropolitan areas. Such upheavals may be explained if the advantage of established urban centers rests on localized learning-by-doing. When a new technology for which this accumulated experience is...

Much recent work has suggested that endogenous technological change tends to reinforce the position of the leading nations. Yet from time to time this leadership role shifts. We suggest a mechanism that explains this pattern of -leapfrogging- as a response to occasional major changes in...

When a country is the recipient of large-scale, politically motivated immigration -- as has been the case for Israel in recent years -- the initial impact is to reduce real wages. Over the longer term, however, the endogenous response of investment, together with increasing returns, may well...