Agglomeration
node
The measured tendency for firms and workers to be more productive when there are more of them nearby. It is the reason cities exist at all, and it is a network effect rather than a design property: the value of being in a city comes from the other people already in it, which is why it cannot be laid out in advance the way a road can. The empirical literature summarised by Rosenthal and Strange puts the elasticity of productivity with respect to city size in a fairly narrow band — roughly 3 to 8 per cent for a doubling of size in most estimates, with French and US wage-elasticity estimates near 0.03 and 0.043. Three mechanisms are usually distinguished: sharing of inputs and infrastructure, better matching between workers and jobs, and learning through proximity. Two features matter for this Journey. The effects decay steeply with distance — they are neighbourhood-scale, not metropolitan-scale — and they are a property of accumulated density, which is exactly what a new-build city does not have on opening day.
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Assembled narrative · 1
Assembled from 21 blocks · 1 evidence · 22 related
- Story
- The measured tendency for firms and workers to be more productive when there are more of them nearby. It is the reason cities exist at all, and it is a network effect rather than a design property: the value of being in a city comes from the other people already in it, which is why it cannot be laid out in advance the way a road can. The empirical literature summarised by Rosenthal and Strange puts the elasticity of productivity with respect to city size in a fairly narrow band — roughly 3 to 8 per cent for a doubling of size in most estimates, with French and US wage-elasticity estimates near 0.03 and 0.043. Three mechanisms are usually distinguished: sharing of inputs and infrastructure, better matching between workers and jobs, and learning through proximity. Two features matter for this Journey. The effects decay steeply with distance — they are neighbourhood-scale, not metropolitan-scale — and they are a property of accumulated density, which is exactly what a new-build city does not have on opening day.
- Knowledge
- Twenty-first-century urbanisation
- Agglomeration
- Connections
- Twenty-first-century urbanisation
- Urban mass transit
- Songdo
- Songdo passes 200,000 residents — and stays short on jobs
- Degree of Urbanisation
- Sub-Saharan African urban growth
- Agglomeration
- Urban cooling demand
- The world is reported to become majority urban
- Nigeria's census is postponed again
- The JMP reports flat urban water coverage
- World Urbanization Prospects 2025 changes the measurement
- Where the next billion city dwellers are projected to be
- Evidence
- Supports the statement that estimated productivity elasticities with respect to city size cluster in the low single digits to about 8 per cent per doubling, with US and French wage elasticities near 0.043 and 0.03, and that agglomeration effects decay sharply with distance. V55 verification basis: retrieved from summaries and abstracts of this literature; none of the chapters or papers was opened.
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No public Signals are attached to this object. Signals show what changed and when it was observed — never a direction or a rank.
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