Clusters, Heritage and the Microfoundations of Spillovers - Lessons from Semi-Conductors

知识产业往往在地理上聚集，这一直被认为是通过相互竞争的公司的当地员工交换技术诀窍和更换雇主来促进知识溢出。现有公司的员工有时还会找到自己的剥离公司，这可能是知识溢出的一个来源。智力价值：拟议工作的主要目的是在半导体行业的背景下评估这些替代溢出机制的强度及其对公司业绩的影响，半导体行业以聚集在硅谷而闻名，其次是波士顿、纽约和洛杉矶。理清这些替代机制的重要性是至关重要的；如果集群促进知识交换和员工流动，那么集群对社会是有益的，而如果剥离是集群的主要渠道，那么集群的好处不会延伸到剥离和它们的“父辈”之外。使用年度买家指南，收集所有半导体生产商从该行业成立到1987年的地点和产品的数据。收集公司的销售数据以确定市场领先者。每一家生产商的进入前经验都会被追踪，使用年度买家指南来确定其他电子产品生产商的以前的生产商，并使用贸易期刊和网络来源来确定衍生产品及其母公司。收集分配给每个半导体生产商和专利发明者的专利，以追踪发明者随着时间的推移的流动性。分析了区位等因素对半导体生产商是否在技术前沿进入半导体产品生产，如果不是，是否在以后转向生产前沿产品的影响。分析了发明者流动性的决定因素，包括发明者在集群中的流动性是否更大。在样本期内开发了各种新的半导体产品，并对影响公司是否采用新产品的因素进行了分析，包括地点的作用。所有这些决策反过来都与企业的业绩有关，反映在它们的销售额和寿命上。更广泛的影响：了解集群是否能改善企业业绩，以及区域知识传播背后的主要机制，可以对战略和政策产生重要的更广泛的影响。如果集群化促进了直接的知识共享和企业间的员工流动，进而促进了集群化，那么集群化具有明显的福利效益，也会使集群中的企业受益。或者，如果剥离是集聚的主要渠道，那么外部经济就不会超越剥离及其“父母”和集聚，而集聚本身不会为集群中的公司提供任何社会利益或任何私人利益。

Knowledge industries tend to cluster geographically, which has long been thought to promote spillovers of knowledge through local employees of competing firms exchanging know-how and changing employers. Employees of incumbent firms also sometimes found their own spinoff firms, which can be a source of knowledge spillovers. Intellectual Merit: The main purpose of the proposed work is to assess the strength of these alternative spillover mechanisms and their effect on firm performance in the context of the semiconductor industry, which famously clustered in Silicon Valley and secondarily in Boston, New York, and Los Angeles. Sorting out the importance of these alternative mechanisms is critical; if clusters promote knowledge exchange and employee mobility then clustering is socially beneficial whereas if spinoffs are the primary conduit for clustering then the benefits of clusters do not extend beyond spinoffs and their 'parents'. Using an annual buyers' guide, data are collected on the location and products of all semiconductor producers from the inception of the industry through 1987. Firm sales data are collected to identify the market leaders. The pre-entry experience of each producer is traced using the annual buyers' guides to identify prior producers of other electronics producers and trade journals and web sources are used to identify spinoffs and their parents. The patents assigned to each semiconductor producer and the inventors of the patents are collected to trace the mobility of the inventors over time. An analysis is conducted of the influence of location and other factors on whether semiconductor producers entered producing semiconductor products at the technological frontier, and if not whether they later shifted to produce frontier products. The determinants of the mobility of inventors are analyzed, including whether mobility was greater for inventors in clusters. Various new semiconductor products were developed in the sample period, and analyses are conducted of the factors influencing whether firms adopted new products, including the role of location. All of these decisions are in turn related to the performance of firms, as reflected in their sales and longevity.Broader Impact: Understanding whether clusters improve firm performance and the main mechanisms behind regional knowledge diffusion can yield important broader impacts for both strategy and policy. If direct knowledge sharing and inter-firm employee mobility are promoted by clustering and in turn contribute to clustering, then clustering has clear welfare benefits and would also benefit firms located in clusters. Alternatively, if spinoffs are the primary conduit for clustering, then external economies do not go beyond spinoffs and their 'parents' and clustering provides no social benefits per se nor any private benefits to firms located in clusters.