QUANTIFYING THE SCOPE FOR EFFICIENCY DEFENSE IN MERGER CONTROL: THE WERDEN‐FROEB‐INDEX*
提出Werden-Froeb指数，用于衡量横向并购后为恢复并购前均衡价格和数量所需的边际成本加权平均降幅，作为集中度指标的补充，帮助评估并购效率。
This paper introduces the Werden‐Froeb Index (WFI) to assist in evaluating merger‐specific efficiencies in horizontal mergers. The index measures the weighted average reduction in marginal costs required to restore pre‐merger equilibrium prices and quantities after the (full or partial) merger is consummated. The WFI is well defined, objective and robust, and it has relatively low information requirements. We propose to use the index as a natural complement to concentration measures such as the Hirschmann‐Herfindahl Index in the assessment of horizontal mergers.