Understanding the economic and social effects of the recent global trends of rising market concentration and market power has become a policy priority. To fill this knowledge gap, this paper introduces a simple simulation method, the Welfare and Competition tool (WELCOM), to estimate with...

Understanding the economic and social effects of the recent global trends of rising market concentration and market power has become a policy priority, particularly in developing countries where markets are often more concentrated. In this context, since the poor are typically the most affected...