Corrado Benassi

The new Keynesian economics

Preface 1. From Keynesian to New Keynesian economics. 2. Keynesian microfoundations in historical perspectives. Part I Real Rigidities 3. The labour market and real wage rigiditry. 4. Credit rationing and imperfect capital markets. 5. Real rigidities in the goods market. Part II Nominal Rigidities Introduction 6. Rational models of irrational behaviour. 7. Price setting with adjustment cost. 8. Real and nominal price rigidity: further issues. Part III Coordination Failures and Hysteresis 9. Coordination failures 10. Hysteresis Conclusions.

Vertical Differentiation and the Distribution of Income

The paper analyses the effects of income concentration on the behaviour of a duopoly with vertical product differentiation and uncovered market. By using a trapezoid distribution, we solve explicitly for market equilibrium as a function of a mean preserving spread of the income distribution. We show that overall more concentrated incomes imply stronger product differentiation, as the presence of a large share of middle-income consumers stimulates a price competition, whose effects are dampened through an enlargement of the quality spread. While the high-quality advantage and market coverage increase unambiguously in the degree of income concentration, the behaviour of prices is non-monotone in the distribution parameter.

Indexation Rules, Risk Aversion and Imperfect Information

Nominal wage adjustment is modeled as resulting from bargaining between a risk neutral firm and a risk averse worker, in an environment where the rate of inflation is a random variable. Risk aversion makes for endogenous indexation arrangements, which deliver partial indexation as they exploit imperfect inflation indices; risk aversion also generates a positive correlation between indexation and inflation variance. The model suggests a distinction between complete vs incomplete inflation adjustment on the one hand, and perfect vs imperfect adjustment on the other hand.

Income Share Elasticity and Stochastic Dominance

Income share elasticity is a function π which can describe the size distribution of income (Esteban in Intern Econ Rev 27:439–444, 1986). On the other hand, the conventional density representation of the latter gives parameters of first or second order stochastic dominance (SD), widely used to describe shifts in income distribution, to which inequality measures are attached. The paper draws a link between the two, by providing conditions such that a given shift to π is equivalent to a first or second order SD shift of the distribution of income. Some applications to Lorenz rankings are also provided.

Market power under income polarization

We study the reaction of a monopolistic firm to distributive shocks which lead to income polarization. We show that the movements in the set price and in the sold quantity depend on the served market share. In particular, we identify a region of parameters where the optimal markup moves in the opposite direction of market demand: in this respect, distributive shocks can provide an explanation for countercyclical movements of the markup.

Beyond the Uniform Distribution: Equilibrium Prices and Qualities in a Vertically Differentiated Duopoly

The paper proves the existence of a subgame perfect Nash equilibrium in a vertically differentiated duopoly with uncovered market, for a large set of symmetric and asymmetric distributions of consumers, including, among others, all logconcave distributions. The proof relies on the ’income share elasticity’ representation of the consumers’ density function, which ensures the analytical tractability of the firms’ optimality conditions at a high level of generality. Some illustrative examples of the solution are offered, in order to assess the impact of distributive shocks on the equilibrium market configuration.

Personal income distribution and market structure

Income distribution aects demand and its elasticity, and, as a consequence, the optimal behaviour of …rms and market equilibrium. This paper focuses on the eects of income polarisation, and presents a model where - for any unimodal density function describing income distribution of the consumers - income polarisation leads to market concentration, i.e., to a smaller number of …rms able to survive in the long run, provided that the

Optimal Commodity Taxation and Income Distribution

We consider the interplay between income distribution and optimal commodity taxation, linking equity issues to optimal taxes through the effect of income distribution on market demand and its price elasticity. We find conditions to conciliate the equity and efficiency tradeoff and to assess the impact of inequality changes on the optimal taxation of necessity and luxury goods. We show that the regressivity or progressivity of the tax system is determined by the distribution of luxuries and necessities in the economy. If the tax system is regressive (progressive), a decrease (increase) of income inequality leads to an average decrease of the optimal tax rates, achieving welfare gains for society. Our analysis provides a framework to investigate the linkages between direct and indirect taxation.

A Note on Income Share Elasticity and Stochastic Dominance

Esteban (1986) introduced the notion of income share elasticity as a function pi which can describe the size distribution of income. On the other hand, indices of first or second order stochastic dominance are widely used to describe shifts in income distribution, to which inequality measures are attached. The paper draws a link between the two, by providing conditions such that a given shift to pi is equivalent to a first or second order stochastic dominance shift of the distribution of income.

Income Distribution and Monopoly: Price and Quantity Patterns with Intra- and Inter-class Income Dispersion

We analyze the direction of the co-movements of price and output in a monopolistic market when an expansive shock occurs. Price and quantity patterns are shown to depend on the consumers? income distribution. In particular, a low degree of income dispersion is associated with price and quantity reacting in opposite directions to demand shocks.