I discuss the impact of tying, bundling, and loyalty/requirement rebates on consumer surplus in the affected markets. I show that the Chicago School Theory of a single monopoly surplus that justifies tying, bundling, and loyalty/requirement rebates on the basis of efficiency typically fails....

We discuss strategic ways that sellers can use tying and bundling with requirement conditions to extract consumer surplus. We analyze different types of tying and bundling creating (i) intra-product price discrimination; (ii) intra-consumer price discrimination; and (iii) inter-product price...

We examine the intersection of patents and antitrust where a patent holder uses the monopoly power it possesses in the market for a patented product to exclude competitors in an adjacent market and attempt to monopolize or monopolize the adjacent market. The present scheme for awarding patents...

This paper asks how much the strength of network effects depends on the stability and structure of the underlying social network. I answer this using extensive micro-data on all potential adopters of a firm's internal video-messaging system and their subsequent video-messaging. This firm's New...

We model a two-sided market with heterogeneous customers and two heterogeneous network effects. In our model, customers on each market side care differently about both the number and the type of customers on the other side. Examples of two-sided markets are online platforms or daily newspapers....

We study a retail benchmarking approach to determine access prices for interconnected networks. Instead of considering fixed access charges as in the existing literature, we study access pricing rules that determine the access price that network i pays to network j as a linear function of the...

We develop a structural econometric framework that allows us to simulate the effects of mergers among two-sided platforms selling differentiated products. We apply the proposed methodology to the Dutch newspaper industry. Our structural model encompasses demands for differentiated products on...

Signal quality is a significant contributor to the overall quality of wireless telephone service, which competitive analyses often overlooks. To understand the competitive impact of signal quality investment on further consolidation in this industry, I use a market research survey of choice of...

Competition among multi-store chains is common in retail industries. This paper proposes a method for estimating a model of strategic store-network choices by two chains. In contrast to previous studies, I allow chains to not only choose which markets to enter but also how many stores to open in...

I discuss the design and implementation of a SSNIP test in order to identify the relevant market in a media market. I argue that in such a two-sided market the traditional SSNIP test cannot be applied as it is usually conceived but rather should be modified in order to take into account indirect...