本文基于软件与信息服务企业的微观截面数据，应用Tobit模型，检验了研发投入与企业规模、所有制类型及政府补贴等因素的关系。研究发现，研发投入与企业规模存在U型关系，国有企业同其他类型企业相比，在研发投入上未表现出显著差异，企业年龄、企业利润率与研发投入具有显著的负向关系，政府补贴有利于企业研发投入，出口、资本密集度对企业研发投入无显著性影响。

Using Software and information service enterprises Cross section data and Tobit model, this paper tests the relationship of the R&D and influence factors, including enterprise scale, ownership type, government subsidy etc. We find that R&D investment and enterprise scale has a U-type relationship, there is no significant difference between the SOE and other ownership types enterprises in the R&D investment, age and profit rate have significant negative effect on the R&D, government subsidy is benefit to the R&D, export and capital intensity have no significant relationship with the R&D investment.