About AMA

Executive Summary
Using data from 50 U.S. markets, Bronnenberg, Dhar, and Dubé (2007) observe that geographic variation is the predominant source of variation in national brand market shares. Moreover, this cross-sectional variation is much larger than cross-time variation. The authors extend this surprising and previously undocumented result in several respects.

First, they seek to assess whether this result generalizes to other markets—in particular, to France. France is an especially desirable market to contrast with the United States because more than one-third of its retail chains and the bulk of its advertising are nationally oriented. The authors replicate this basic finding in France and find that is robust to the sampling rate of the data (weekly or every four weeks), the duration of the data (39 or 66 four-week periods), and the level of aggregation (9, 22, or 96 regions).

Second, similar to Bronnenberg, Dhar and Dubé (2007), the authors find that market shares exhibit spatial dependence. However, the spatial dependency in market shares is less in France. The authors argue that lower levels of spatial dependency may be due to greater regional heterogeneity in customs and culture in France than in the United States.

Third, because of regional variation in chain locations and the limited research regarding the relative effect of chains on market shares, the authors link chain effects to market shares in France. The authors find that (1) chain effects explain more variation in market share than either time or region effects and (2) the addition of chain effects attenuates region-specific effects. Thus, chain structure is both another source of regional variation in demand and an important consideration in its own right.

Finally, by coupling brand–time effects with longer data, the authors note that brand–time effects are as large as brand–region effects in France. This result suggests the importance of long-term effects in marketing and the need to collect longer durations of data to explain variation in market shares.

Biography
M. Berk Ataman is Assistant Professor of Marketing in the Rotterdam School of Management at Erasmus University, the Netherlands. He received his BSc and MSc in Engineering Management from Istanbul Technical University and concluded his doctoral studies at Tilburg University. He held research positions at Tilburg University and Istanbul Technical University before joining Rotterdam School of Management. His research interests include managing marketing activity with a long-term focus and the dynamics of performance and market response.

Carl F. Mela is a Professor of Marketing at Duke University. He received his BScB from Brown University, his MBA from University of Calofornia, Los Angeles, and his MPhil and PhD from Columbia University. Before coming to Duke, he held management positions at Hewlett-Packard, Hughes, and Proxima. Professor Mela’s research focuses upon the long-term effects of marketing activity, customer management, and the Internet. Articles along these lines have appeared in Journal of Marketing Research, Marketing Science, and Journal of Consumer Research, among other journals. Professor Mela has received nine best-paper awards from the Marketing Science Institute, INFORMS, the American Marketing Association, and other professional organizations. He serves on the editorial boards of Journal of Marketing, Journal of Marketing Research, Marketing Science, Marketing Letters, Quantitative Marketing and Economics, and Journal of Public Policy & Marketing. His home page is located at http://faculty.fuqua.duke.edu/~mela/bio.

Harald J. van Heerde is Professor of Marketing at the University of Waikato, Hamilton, New Zealand. He holds an MSc in Econometrics (cum laude) and a PhD (cum laude) from the University of Groningen, the Netherlands. His work has appeared in Journal of Marketing Research, Marketing Science, and Quantitative Marketing and Economics, among other journals. His research has dealt with building econometric models in various substantive domains, such as sales promotions, pricing, and new product introductions, and it is branching out into new areas, such as building brand equity, loyalty programs, assortment optimization, and price wars. His work has been awarded the Paul Green Award in 2004, and it has been a finalist for the Paul Green Award three more times, for the O’Dell Award twice, and for the Frank Bass Award twice. Van Heerde serves on the editorial board of Journal of Marketing Research.