This paper considers the empirical assessment of the relationship between prices and number of firms in local markets in geographic or, more generally, characteristic space and its use as evidence in merger cases. It outlines a structural, semi-nonparametric econometric model of competition in...

This paper studies regulatory policy interventions aimed at protecting vulnerable consumers who are disengaged and thus exposed to exploitation. We model heterogeneous consumer switching costs alongside asymmetric market shares. This setting encompasses many markets in which established firms...

The presence of sticky, often labelled ‘unengaged', consumers is arguably one of the most intractable issues faced by competition regulators, in that it entrenches incumbency advantage. We develop a spatial linear model of heterogeneous switching costs that allows for asymmetric distributions...