Comment on “A note on the Hotelling principle of minimum differentiation: Imitation and crowd”

We argue that the minimum differentiation firm location equilibrium and the pure strategy pricing equilibrium in Di Cintio’s [Di Cintio, M., 2007. A note on the Hotelling principle of minimum differentiation: Imitation and crowd. Research in Economics 61 (3), 122–129] “Note” need not exist under the conditions claimed.     

A note on the Hotelling principle of minimum differentiation: Imitation and crowd

This paper investigates price competition in the Hotelling location model with linear transportation costs when consumer preferences are affected by the number of consumers shopping at the same store. A consumption externality permits us to consider the imitation and the congestion effects which are opposite forces at work. The coexistence of the two effects confers new validity to the principle of minimum differentiation as it was in the original Hotelling model. I show that firms do not need to set apart in order to earn higher profits. The results show firms endogenously choosing to locate in the center of the interval sharing the market with positive prices.     

Wages,selectivity, and vacancies: Evaluating the short-term and long-term impact of the minimum wage on unemployment

Using a circular matching model (Marimon R, Zilibotti F. Unemployment vs. mismatch of talents: Reconsidering unemployment benefits. Economic Journal 1999;109; 266–291), where the wage setting is similar to Weiss (Weiss A. Job queues and layoffs in labor markets with flexible wages. Journal of Political Economy 1980; 88; 526–538), we reexamine Card and Krueger's (Card, D., Krueger, A. Myth and Measurement, the New Economics of the Minimum Wage. Princeton University Press; 1995) intuition on the impact of the minimum wage on unemployment. In the short term, a rise in the minimum wage increases the employment level by making firms less selective. In the long term, numerical simulations show that, despite the reduction of job creation, introducing a minimum wage may lower unemployment as soon as workers and jobs are sufficiently differentiated. However, beyond some limit, the wage increase raises unemployment whatever the degree of differentiation is.     

PRICE FLOORS AND QUALITY CHOICE

This paper studies effects of price floors in a simple model of vertical product differentiation. We find that even non‐binding price floor (i.e., minimum price set below the lowest Nash equilibrium price in the baseline model) can increase quality on the market, if the cost of quality is sufficiently low. Where a binding price floor does not increase the equilibrium quality, it makes consumers worse off. There is also a possibility of over‐investment into quality as a result of the binding minimum price.     

Positive- versus zero-sum majoritarian ultimatum games: An experimental study

Politics can involve a movement from a position off the Pareto frontier to a point on it (a positive-sum game as exemplified in the classic [Buchanan, J.M., Tullock, G., 1962. The Calculus of Consent. University of Michigan Press, Ann Arbor] work), or a movement along the Pareto frontier (a zero-sum game as exemplified in the classic [Riker, W., 1962. The theory of political coalitions. Yale University Press, New Haven] work). In this paper we shed light on their differentiation experimentally by making a comparison between a positive-sum and a zero-sum majoritarian ultimatum game. Our main findings include (i) the fraction of subjects who adopted minimum winning rather than oversized coalitions increases significantly as the game form varies from positive-sum to zero-sum, (ii) oversized coalitions are attributable to non-strategic considerations, and (iii) subjects who choose to adopt the minimum winning coalition have a tendency to seek cheaper responders as their partners in the zero-sum game, but there is no evidence of such a tendency in the positive-sum game. Overall, the weight of the evidence revealed by our experimental data indicates that relative scarcity (embodied in the zero-sum game) promotes behavior more in line with the predictions of economics.     

The dynamics of a differentiated duopoly with quantity competition

We analyse the dynamics of a Cournot duopoly with heterogeneous players to investigate the effects of micro-founded differentiated products demand on stability. The present study, which indeed modifies and extends Zhang et al. (2007) (Zhang, J., Da, Q., Wang, Y., 2007. Analysis of nonlinear duopoly game with heterogeneous players. Economic Modelling 24, 138–148) and Tramontana, F., (2010) (Tramontana, F., 2010. Heterogeneous duopoly with isoelastic demand function. Economic Modelling 27, 350–357), reveals that a higher degree of product differentiation may destabilise the market equilibrium. Moreover, we show that a cascade of flip bifurcations may lead to periodic cycles and ultimately chaotic behaviours. Since a higher degree of product differentiation implies weaker competition, then a theoretical implication of our findings, that also constitute a policy warning, is that a fiercer (weaker) competition tends to stabilise (destabilise) the unique positive Cournot–Nash equilibrium.     

Location models as models of product choice

Markets in which firm choice of product is an economic decision are commonly analyzed using a variant of the location model pioneered by Hotelling (Econ. J.39 (1929), 41–57). This paper develops a framework for formalizing the idea that a set of consumers with preferences defined over an abstract set of commodities can be represented as if they behaved as is typically assumed in the goods-as-locations models. With this framework in place, we are able to derive the preference assumptions underlying the two most common versions of these models, and also to uncover the foundations of the now well-known principle of minimum differentiation.     

Differentiated industries without entry barriers

Our objective is to predict the evolution of an industry without entry barriers where products are differentiated on the basis of quality. Each firm chooses a single brand whose characteristics and amount of production is determined by the firm. The analysis suggests two different stages in the evolution. The first is a stage of growth and the second is a stationary stage in terms of aggregate production. While during the first stage the entry of additional brands results in the reduction of average quality, during the second stage entry leads to increased average quality. Hotelling's principle of “minimum differentiation” is contradicted in the model.     

基于产品差别理论的电视节目类型趋同研究

本文建立了一个空间竞争模型分析电视节目类型趋同现象。节目类型的趋同意味着频道间节目的水平差别变小,而电视节目差别的的实质是产品差别。如果将观众的效用函数设定为节目类型距离的线性函数,电视频道间节目的水平差别必然实现最小化,节目类型完全相同。     

Location choices and third‐degree spatial price discrimination

This paper studies how firms choose their product differentiation levels when they engage in third‐degree price discrimination in the following product market competition in a location‐price model. We show that firms will not choose to locate at the two endpoints if different consumer groups have similar sizes. Hence, the principle of maximum differentiation does not hold, resulting in a more intense product market price competition. Only if the size of one group of consumers is sufficiently larger than that of the other group, would firms make their products as differentiated as possible by choosing the two endpoints as their locations.     

Optimal punishments in linear duopoly supergames with product differentiation

We analyze optimal penal codes in both Bertrand and Cournot supergames with product differentiation. We prove that the relationship between optimal punishments and the security level (individually rational discounted profit stream) depends critically on the degree of supermodularity in the stage game, using a linear duopoly supergame with product differentiation. The security level in the punishment phase is reached only under extreme supermodularity, i.e., when products are perfect substitutes and firms are price setters. Finally, we show that Abreu's rule cannot be implemented under Cournot behavior and strong demand complementarity between products.     

Tariffs,Quality Choice,and Cost Functions: a Foreign Monopoly Case*

It has been shown that trade restrictions such as tariffs, import quotas, and voluntary export restrictions, lead to quality upgrading of imports. In this paper, however, we reconsider this proposition by focusing on the nature of cost functions. Based on a standard vertical differentiation model, we analyze the effects of tariffs on quality and quantity of imports. We show that if a fixed cost is an increasing function of quality, tariffs lead to quality downgrading of imports. Moreover, we discuss minimum quality requirements (MQR) for such a trade policy. We show that MQR increases the amount of imports and an importing country's welfare in the presence of the fixed cost function. These issues will be addressed in the context of a foreign monopoly.     

Simultaneity between strategic variables: Production,innovation, and product differentiation

This paper aims to analyze the existence of simultaneous effects among the variables production, product differentiation, and innovation. Microeconomic data from a sample of 2,160 firms are used as a base. Empirical results show that a positive correlation exists from innovation to product differentiation, thus showing that it is in the process of production itself, through technical improvements, where product differentiation is determined. On the other hand, no positive effect exists from product differentiation to innovation, i.e., once technical improvements have been established, firms exchange the barriers to entry created by brand image for the real barriers established by innovation itself. Lastly, the importance of the firm size in explaining the other endogenous variables analyzed is confirmed. This paper has received financial support from the Valencian Institut of Economic Research (IVIE). The study was carried out within the framework of research program SEC94-1357 of the Comisón Interministerial de Ciencia y Tecnología (CICYT).     

On the political economy of zoning

Households choose a community in a metropolitan area and collectively set a minimum housing quality and a property tax to finance a local public good. The collective imposition of a lower bound on housing consumption induces an income-stratified equilibrium in a specification where meaningful community differentiation would not arise without zoning. We show computationally that zoning restrictions are likely to be stringent, with a majority facing a binding constraint in communities that permit it. By inducing a stratified equilibrium, zoning causes Tiebout-welfare gains in aggregate but with large welfare transfers. Relative to stratified equilibrium without zoning, the zoning equilibrium is significantly more efficient as it reduces housing-market distortions.     

Weak and Strong Signals

Akerlof, Spence and Stiglitz showed that competitive markets can perform very poorly in the presence of informational asymmetry. In this paper I show that if there is a signaling technology which is sufficiently strong (i.e., the marginal cost of signaling declines sufficiently rapidly with quality) the cost of sorting is low and a Nash equilibrium exists. Empirically testable necessary and sufficient conditions for existence are derived. I further show that if Akerlovian participation constraints are added to a signaling model there is a minimum signaling threshold. Finally I argue that these conclusions hold regardless of whether it is the uninformed or informed agents who move first.
JEL classification : D 8     

Voting requirements, concessions, international side payments and the European Monetary Union

This paper addresses the question of criteria for selection of EMU members. We identify two factors in the decision process: (1) The costs and benefits which the individual countries attribute to alternative EMU arrangements (`hard-core', medium-sized, all EU members), and (2) the binding institutional restrictions, i.e., the distribution of votes in the European Council and the minimum vote requirements. Within this framework the EU countries are assigned to different groups according to their degree of convergence. Based on stability concessions and side payments these groups decide on the final EMU composition. We show that minimum vote requirements can lead to a suboptimal size of the EMU and can threaten the feasibility of a multi-speed monetary union.     

Monetary Policy and Market Power in Banking

Applying a spatial competition model to banking, we analyze the effects of the choice of a monetary policy rule by the central bank on banks market power as measured by the Lerner index. We show that a procyclical monetary policy may reinforce the countercyclical movement of the Lerner index. That is, this measure of competitiveness of the banking sector may vary more over the business cycle due to the monetary policy rule.JEL classification: G21, E52, L13.Acknowledgements The author thanks Hans Degryse, Hans van Ees, Marco Haan, Eko Riyanto, Bert Schoonbeek, Elmer Sterken, three anonymous referees, and participants of the EARIE 2001 conference (Dublin), the NAKE Day 2002 (Amsterdam), and a seminar at Ghent University for their constructive comments.revised version received November 11, 2003     

Reforming the dutch welfare state: A scenario approach

The Dutch social protection system has been under reconstruction since the early 1980s. After describing the structure of the current system and addressing recent developments as to the treatment of families and individuals, this paper presents three scenarios that could develop in future years. In full individualization, benefits and conditions are attuned to individual citizens without considering their care for others and the financial means of others in their household. In a mini-system, statutory benefits are restricted to some minimum level. In further differentiation of the social minimum by household size, benefits are better attuned to the composition and size of household types. These three scenarios are evaluated based on four criteria. The differentiation scenario appears to meet nearly all criteria and seems to offer a new solution for the problem of the weak income position of households with children relative to other household types on the minimum income level.The author would like to thank David Rasmussen for his valuable comments on an earlier version of this paper.     

Investment and technological choice in a right-to-manage model

We analyze the interactions between investment and local wage bargaining in a putty-clay model where the investment decision commits the firm to a particular capital intensity. This technological precommitment is used strategically in order to manipulate the bargaining outcome. We show that this strategic behavior induces a nonmonotonic relationship between the capital and labor demands of the firm and most of its environmental parameters (e.g., the bargaining power of the union, its minimum wage requirement, the capital cost). The results we obtain in our putty-clay framework thus contradict several conclusions of the standard literature on wage bargaining and investment.     

Minimum standards, insurance regulation and adverse selection: evidence from the Medigap market

This paper examines the implications of minimum standards for insurance markets. I study the imposition of binding minimum standards on the market for voluntary private health insurance for the elderly. The central estimates suggest that the introduction of the standards was associated with an 8 percentage point (25%) decrease in the proportion of the population with coverage in the affected market, with no evidence of substitution toward other, unregulated sources of insurance coverage. To explore possible factors contributing to the impact of the minimum standards, I develop comparative static predictions of the impact of imposing minimum standards in an insurance market with adverse selection. The observed changes in market equilibrium associated with the minimum standards are broadly consistent with these predictions, providing evidence of the existence of adverse selection in this insurance market. More importantly, they suggest that the presence of adverse selection—which in principle may provide an economic rationale for minimum standards—in practice may have exacerbated the declines in insurance coverage associated with the minimum standards.