Many industries are geographically concentrated. Many mechanisms that could account for such agglomeration have been proposed. We note that these theories make different predictions about which pairs of industries should be coagglomerated. We discuss the measurement of coagglomeration and use...

"Fragmentation of stages of the production process is determined by international cost differences and by the benefits of co-location of related stages. The interaction between these forces depends on the technological relationships between these stages. This paper looks at both cost minimising...