This paper is concerned with the Wider Economic Impacts (WEIs) of transport improvements that arise via scale economies of agglomeration. It reviews the background theory and empirical evidence on agglomeration, explains the link between transport and agglomeration, and describes a three step procedure to appraise agglomeration impacts in a number of different settings. It includes new analytical work on measures of agglomeration and reports agglomeration-productivity elasticity estimates for the UK not previously published in the academic literature. The paper concludes with a set of recommendations for future empirical work on agglomeration and transport appraisal.

中文翻译：

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量化集聚对运输评估的更广泛的经济影响：现有证据和未来方向

本文关注的是通过集聚规模经济而产生的交通运输改善对经济的广泛影响。它回顾了集聚的背景理论和经验证据，解释了运输与集聚之间的联系，并描述了一个三步法来评估在许多不同环境下的集聚影响。它包括有关集聚量度的新分析工作，并报告了以前未在学术文献中发表的英国的集聚生产率弹性估计值。最后，本文针对集聚和运输评估的未来实证工作提出了一系列建议。