Estimating the degree of firms’ input market power via data envelopment analysis: Evidence from the global biotechnology and pharmaceutical industry
该研究基于数据包络分析提出投入市场勒纳指数，用于估计企业投入市场势力，并分析研发投入对市场势力的非线性影响，对全球生物技术和制药企业有参考价值。
This study estimates input market power by introducing an input-market-based Lerner index based on data envelopment analysis (DEA). This index is an extension to the DEA-based Lerner index. In doing so, we develop a revenue function, which is based on minimum distance framework. DEA based-Lerner indexes are commonly based on efficiency measures aiming at finding the “farthest” strongly efficient point. However, if firms operate in non-optimal scales, then such a methodological treatment can be restrictive. In our case, we adopt the minimum distance. We utilize a strongly revenue-efficient frontier and model a DEA based Lerner index which is less restrictive. We apply our index to a sample of global biotechnology and pharmaceutical (B&P) firms over the period 2015–2019. We further investigate the effect of firms’ research and development (R&D) on firms’ market power estimated by the input-market DEA-based Lerner indexes. Our findings suggest that the investment on R&D has a nonlinear effect on firms’ market power. Finally, our finding suggest that the positive effect of R&D is more pronounced on the estimated firms’ employees-based market power compared to the asset-based market power index.