Abstract:
This paper shows, using data from both the US and the UK, that average plant size is larger indenser markets. However, many popular theories of agglomeration - spillovers, costadvantages and improved match quality - predict that establishments should be smaller incities. The paper proposes a theory based on monopsony in labour markets that can explainthe stylized fact - that firms in all labour markets have some market power but that they haveless market power in cities. It also presents evidence that the labour supply curve toindividual firms is more elastic in larger markets.