在看论文的时候看到：The World Bank has undertaken large numbers of firm level surveys with the express intention of measuring the quality of the “business environment” or the “investment climate.”This database has information on 49,584 manufacturing and service firms from 71 countries around the world for 2002-2005, of which 46,429 are not publicly traded on stock exchanges.
想请问这个世界银行投资环境调查通过什么途径取得呢？我试着在世界银行的网站上搜索，找到的数据都是国家层面的，没有找到企业层面的。第一次发帖，请各位大神帮忙！