Walmart is one of the most successful companies in the world. With more than $ 524 billion in 2020 revenue and 2.2 million employees, Walmart is the world's largest company by sales volume and is ranked 19th on the Forbes list of the world's largest public companies. Walmart serves nearly 265...

The impact of product variety on welfare has received little attention in the electronic commerce literature. The problem with product variety is that more variety does not necessarily imply higher welfare. This paper finds the conditions under which more variety, if caused by lower fixed costs,...

This paper adds two elements to a standard model of monopolistic competition: First, the number of potential entrants is limited in each period and increases only over time. Second, the potential entrants differ with respect to the consumers' valuation of the variant they could offer. It is...

We analyze the gross welfare gains from real-time retail pricing in electricity markets where carbon taxation induces investment in variable renewable technologies. Applying a stylized numerical electricity market model, we find a U-shaped association between carbon taxation and gross welfare...

This paper studies optimal sport league size. League expansion lowers average player quality, reducing fans' utility in inframarginal locations, while fan utility in new locations rises. Welfare analyses of such expansions must compare these two effects. Using a model where fan demand depends on...

When firms form an alliance, it often involves one firm acquiring an equity stake in its alliance partner. Such an alliance weakens competition, but induces knowledge transfer between partner firms. We explore oligopoly models that capture the link between knowledge transfer and partial equity...

This paper shows that self-employment opportunities shape the market power of employers in low-income countries, with implications for industrial development. Using data from Peru, we document substantial employer concentration and high self-employment rates across manufacturing local labor...

Traditional phone carriers have announced ambitious multi-billion dollar plans to bulk up their networks with fiber in order to deliver a range of new services, including multi-channel video in competition with video incumbents. This competition promises to benefit consumers through lower...

Partly motivated by the recent antitrust investigations concerning Google, we develop a leverage theory of tying in two-sided markets. We analyze incentives for a monopolist to tie its monopolized product with another product in a two-sided market. Tying provides a mechanism to circumvent the...

We revisit the relationships between competition and market outcomes in a Stackelberg oligopoly. Consider a differentiated oligopolistic market consisting of n leaders with different efficiencies and m followers. We show that the efficient leader's profit may increase with the number of...