Advertising for attention in a consumer search model

We model the idea that when consumers search for products, they first visit the firm whose advertising is more salient. The gains a firm derives from being visited early increase in search costs, so equilibrium advertising increases as search costs rise. This may result in lower firm profits when search costs increase. We extend the basic model by allowing for firm heterogeneity in advertising costs. Firms whose advertising is more salient and therefore raise attention more easily charge lower prices in equilibrium and obtain higher profits. As advertising cost asymmetries increase, aggregate profits increase, advertising falls and welfare increases.Advertising; attention; consumer search; saliency;

Consumer search costs and the incentives to merge under Bertrand Competition

This paper studies the incentives to merge in a Bertrand competition model where firms sell differentiated products and consumers search the market for satisfactory deals. In the pre-merger market equilibrium, all firms look alike and so the probability a firm is next in the queue consumers follow when visiting firms is equal across non-visited firms. However, after a merger, insiders raise their prices more than the outsiders, so consumers search for good deals first at the non-merging stores and only then, if they do not find any product satisfactory enough, at the merging stores. When search cost are negligible, the results of Deneckere and Davidson (1985) hold. However, as search costs increase, the merging firms receive fewer customers, so mergers become unprofitable for sufficiently large search costs. This new merger paradox is more likely the higher the number of non-merging firms.mergers; search; insiders; outsiders; order of search;

Comparison sites

Web search technologies are fundamental tools for navigating the Internet. One particular type of search technology is "shopbots", or comparison sites. The emergence of Internet shopbots and their implications for price competition and market efficiency are the focus of this paper. We develop a simple model where a price comparison site tries to attract (possibly vertically and horizontally differentiated) online retailers, on the one hand, and consumers, on the other. Analysis of the model reveals that differentiation among the products of the retailers and their ability to price discriminate between on- and off-comparison-site consumers play a critical role. When products are homogeneous, if online retailers cannot charge different on- and off-the-comparison-site prices, then the comparison site has incentives to charge fees so high that some firms are excluded, which generates price dispersion and an inefficient outcome. By contrast, when on- and off-comparison-site prices can be different, the comparison site attracts all the players to the platform and the allocation is efficient. A similar result obtains when products are horizontally differentiated. In that case, the comparison site becomes an aggregator of product information and no matter whether firms can price discriminate or not, the comparison site attracts all the players to the platform and an efficient outcome ensues. We argue that the lack of vertical product differentiation may also be critical for this efficiency result. In fact, we show that when quality differences are large, the comparison site may find it profitable to charge fees that effectively exclude low quality producers, thereby inducing an inefficient outcome.shopbots; two-sided market; intermediation; price discrimination; product differentiation;

On the identification of the costs of simultaneous search

This paper studies the identification of the costs of simultaneous search in a class of (portfolio) problems studied by Chade and Smith (2006). We show that aggregate data from a single market, or disaggregate data from a single market segment, do not provide sufficient information to identify the costs of simultaneous search in any reasonable interval. We then show that by pooling aggregate data from multiple markets, or disaggregate data from multiple market segments, the econometrician can identify the costs of simultaneous search in a non-empty interval. Within the context of specific examples, we illustrate that identification of the search cost distribution in its full support may easily be obtained.search costs; portfolio choice; non-parametric identification;

Nonsequential search equilibrium with search cost heterogeneity

We generalize the model of Burdett and Judd (1983) to the case where an arbitrary finite number of firms sells a homogeneous good to buyers who have heterogeneous search costs. We show that a price dispersed symmetric Nash equilibrium always exists. Numerical results show that the behavior of prices with respect to the number of firms hinges upon the shape of the search cost distribution: when search costs are relatively concentrated (dispersed), entry of firms leads to higher (lower) average prices.nonsequential search; oligopoly; arbitrary search cost distributions;

Search Costs, Demand-Side Economies and the Incentives to merge under Bertrand Competition

This paper studies the incentives to merge in a Bertrand competition model where firms sell differentiatedproducts and consumers search for satisfactory deals. In the pre-merger symmetricequilibrium, the probability that a firm is the next one to be visited by a consumer is equal acrossfirms not yet visited. However, in the short-run after a merger, because insiders raise their pricesmore than what the outsiders do, consumers start searching for good deals at the non-mergingstores. Only when they do not find any product satisfactory enough, they continue searching atthe merging stores. When search costs are sufficiently large, consumer traffic from the non-merging firms to the merged ones is so small that mergers become unprofitable. This new merger paradox,which is more likely the higher the number of non-merging firms, can be overcome in the mediumtolong-run if the merging firms choose to stock their shelves with all the products of the constituent firms, which generates sizable search economies. Such demand-side economies can conferthe merging firms a prominent position in the marketplace, in which case their price may even belower than the price of the outsiders. In that case, consumers visit first the merged entity andthe firms outside the merger lose out. Search cost economies may render a merger beneficial forconsumers and so overall welfare may increase.mergers, insiders, outsiders, short-run, long-run, consumer search, demand-side economies, economies of search, order of search, sequential search, prominence

On the Identification of the Costs of Simultaneous Search

This paper studies the identification of the costs of simultaneous search in portfolio problems (Chade and Smith, 2006). We show that market shares data from a single market do not provide sufficient information to identify the search cost distribution in any interval, even if utilitydistributions are known to the econometrician. We then show that by pooling data from markets wherethe alternatives that similar decision makers confront vary, the search cost distribution and theutility parameters of the logit demand model can be identified.search costs, portfolio choice, non-parametric identification, logit demand