Marc Rysman

Competition between Networks: A Study of the Market for Yellow Pages

This paper estimates the importance of network effects in the market for Yellow Pages. I estimate three simultaneous equations: consumer demand for usage of a directory, advertiser demand for advertising and a publishers first-order condition (derived from profit-maximizing behaviour). Estimation shows that advertisers value consumer usage and that consumers value advertising, implying a network effect. I find that internalizing network effects would significantly increase surplus. As an application, I consider whether the market benefits from monopoly (which takes advantage of network effects) or oligopoly (which reduces market power). I find that a more competitive market is preferable. Copyright 2004, Wiley-Blackwell.

Patents and the Performance of Voluntary Standard Setting Organizations

Voluntary standard-setting organizations (SSOs) are a common feature of systems industries, where firms supply interoperable components for a shared technology platform. These institutions promote coordinated innovation by providing a forum for collective decision making and a potential solution to the problem of fragmented and overlapping intellectual property rights. This paper examines the economic and technological significance of SSOs by analyzing the flow of citations to a sample of U.S. patents disclosed during the standard-setting process. Our main results show that the age distribution of SSO patent citations is shifted toward later years (relative to an average patent) and that citations increase substantially following standardization. These results suggest that SSOs identify promising technologies and influence their subsequent adoption.

An Empirical Analysis of Payment Card Usage

I exploit a unique data set on the payment card industry to study issues associated with network effects and two-sided markets. I show that consumers concentrate their spending on a single payment network (single-homing), although many maintain unused cards that allow the ability to use multiple networks (multi-homing). Further, I establish a regional correlation between consumer usage and merchant acceptance within the four major networks (Visa, Mastercard, American Express and Discover). This correlation is suggestive of the existence of a positive feedback loop between consumer usage and merchant acceptance.

Unobserved Product Differentiation in Discrete Choice Models: Estimating Price Elasticities and Welfare Effects

This document is a supplement to Ackerberg and Rysman (2005). In that paper, we discuss problems with standard techniques for discrete choice estimation in the context of consumers that face different numbers of products. We propose a solution based on adding a function of the number of products to the estimation equation, which we motivate with a model of retail conjestion. Section 6 of the main paper introduces a second solution that allows the variance of the logit error to be smaller in markets with more products. This solution entails a multiplicative adjustment rather than an additive adjustment. Here, we elaborate on the multiplicative solution. We show how this feature can arise from a model in which products in crowded markets differentiate into dimensions that consumers care less about. We provide Monte Carlo analysis and an empirical example.

Dynamics of Consumer Demand for New Durable Goods

Most new consumer durable goods experience rapid prices declines and quality improvements, suggesting the importance of modeling dynamics. This paper specifies a dynamic model of consumer preferences for new durable goods with persistently heterogeneous consumer tastes, rational expectations, and repeat purchases over time. We estimate the model on the digital camcorder industry using panel data on prices, sales, and characteristics. We find that the 1-year elasticity in response to a transitory industrywide price shock is about 25 percent less than the 1-month elasticity. Standard cost-of-living indices overstate welfare gain in later periods due to a changing composition of buyers.

Explaining Adoption and Use of Payment Instruments by U.S. Consumers

The way that consumers make payments is changing rapidly and attracts important current policy interest. This paper develops and estimates a structural model of adoption and use of payment instruments by U.S. consumers. We use a cross-section of data from the Survey of Consumer Payment Choice, a new survey of consumer behavior. We evaluate substitution and income effects. Our simulations shed light on the consumer response to the 2011 regulation of interchange fees on debit cards imposed by the Dodd-Frank Act, as well as the proposed settlement between Visa and MasterCard and the Department of Justice that would allow merchants to surcharge the use of payment cards.

The Economics of Payment Cards

This paper surveys the economics literature on payment cards, focusing on the role of interchange fees, merchant internalization, surcharging and two-sided markets. The paper aims to integrate a wide range of theoretical papers with the relevant empirical research and important policy questions. We address not only the accomplishments of the research so far, but also the most important limitations in the existing theory and gaps where future research should be directed. Drawing on the insights developed, we provide a detailed evaluation of different policy options.

Payment Choice with Consumer Panel Data

We exploit scanner data to track payment choice for grocery purchases for a large panel of households over three years. We show that households focus most of their expenditures on one or at most two of these instruments in choosing between using cash, a check, or a card, and they very rarely switch. We focus particularly on the role of expenditure size in determining payment choice. While the use of a long panel for these purposes is novel, the introduction of controls for household heterogeneity has little effect on our estimates. Thus, we find that transaction size is an important determinant of payment choice, not only across households but within households.

Identifying the Age Profile of Patent Citations

Previous work studying the age distribution of citations for patents relies on functional form assumptions to address the co-linearity between the birth year, citation year, and age. This paper proposes a non-parametric identification strategy that uses the lag between application and grant as a source of exogenous variation. We show empirically that the “citation clock” starts only when a patent issues, and we examine the potential bias if our assumption is incorrect. We use our approach to re-examine some prior results on the citation age profile of patents from different technological fields. We discuss potential extensions into other research areas.

How many franchises in a market

Abstract This paper studies how firms use their number of franchises as a strategic tool. Firms can commit to high output by creating many franchises. However, signing a single franchise contract with a low wholesale price is an equally effective way to generate output. The value of granting many franchises is undercut when firms can sign contracts afterwards, so firms place only a single franchise in a market. This finding reverses previous results which did not model contracts. The same issues arise in international competition policy, where countries use anti-trust policy to affect their number of exporters and use subsidies to affect the choices of exporters.