美国城市的连贯性
Simone Daniotti1,2,3, Matté Hartog4, Frank Neffke1
1Complexity Science Hub Vienna, Vienna 1030, Austria.
概括
城市的目标是经济多样化,但这需要扩大能力. 这项研究表明,城市经济连贯性随着时间的推移而保持稳定,多元化受到城市规模的限制.
科学领域:
- 城市经济学城市经济学
- 经济地理 经济地理
- 复杂性科学 复杂性科学
背景情况:
- 多元化经济对城市的增长和发展至关重要.
- 经济多元化往往需要扩大城市的能力基础,在增长和成本之间进行权衡.
- 了解城市如何管理这种权衡是可持续城市发展的关键.
研究的目的:
- 分析城市如何管理经济多样化与相关成本之间的权衡.
- 测量城市内的经济活动的一致性,作为多样化管理的指标.
- 研究从1850年到现在的美国城市系统的长期发展.
主要方法:
- 将经济连贯性定义和衡量为城市生产单位之间的技术距离.
- 利用历史人口普查数据 (超过6亿条记录) 来分析1850年至1940年的经济活动.
- 分析近几十年的专利记录和详细的职业/工业概况.
主要成果:
- 尽管美国经济地理在170年间发生了重大变化,但平均城市经济连贯性一直保持不变.
- 经济连贯性在不同的时间段和数据集中随着城市规模的不断减少.
- 连贯性和城市规模之间的这种反向关系表明多样化的普遍限制.
结论:
- 城市经济系统在长时间内表现出稳定的连贯性,表明多样化的一致模式.
- 城市规模是对经济多样化的普遍约束,无论特定时代或经济结构如何.
- 未来的城市发展战略应该考虑这些取决于规模的多样化限制.
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