Advanced methods: Identifying the technology profiles of R&D performing firms - a matching of R&D and patent data
In this study, we develop a concordance list between industry sectors and technologies for R&D data that enables us to report business R&D expenditures not only by industries but also by technology fields. For the construction of the concordance, data on R&D expenditures were matched with patent data at the microlevel, i.e., at the level of companies and patent applicants, respectively. The business R&D expenditures were then aggregated at the level of technology fields. This includes a weighting scheme, since it can be assumed that the costs of generating a patent differ across industries and fields. Besides being able to provide R&D data by technology fields, this concordance table also enables us to provide patent statistics at the level of industries. The patent data for the matching procedure were extracted from the ""EPO Worldwide Patent Statistical Database"" (PATSTAT). The data on German business R&D expenditures are provided by the SV Wissenschaftsstatistik. The two data sources are matched by applying a string-matching algorithm based on the distance between two text strings. The matching covers 44% of all German patent applicants and 83% of all patent filings at the EPO and the German Patent and Trademark Office in 2009.