Quality Competition and Social Welfare in Markets with Partial Coverage: New Results*

We use a vertical product differentiation model under partial market coverage to study the social welfare optimum and duopoly equilibrium when convex costs of quality provision are either fixed or variable in terms of production. We show the following new results. First, under fixed costs, the social planner charges a uniform price for the single variant that just covers costs of quality provision. Like the duopoly equilibrium, this socially optimal pricing entails a partially uncovered market, but a smaller share of the market is served compared with the duopoly equilibrium. Second, for the variable cost case, it is socially optimal to provide both high‐ and low‐quality variants, but market shares need not be equal. This differs from the result in fully covered markets. Third, in the duopoly equilibrium, the quality spread is too wide under variable costs relative to the social optimum. Under fixed costs, the duopoly produces two variants, but quality is too low relative to the social optimum, which has only one variant.     

MSE-improvement of the least squares estimator by dropping variables

It is well known that dropping variables in regression analysis decreases the variance of the least squares (LS) estimator of the remaining parameters. However, after elimination estimates of these parameters are biased, if the full model is correct. In his recent paper, Boscher (1991) showed that the LS-estimator in the special case of a mean shift model (cf. Cook and Weisberg, 1982) which assumes no “outliers” can be considered in the framework of a linear regression model where some variables are deleted. He derived conditions under which this estimator outperforms the LS-estimator of the full model in terms of the mean squared error (MSE)-matrix criterion. We demonstrate that this approach can be extended to the general set-up of dropping variables. Necessary and sufficient conditions for the MSE-matrix superiority of the LS-estimator in the reduced model over that in the full model are derived. We also provide a uniformly most powerful F-statistic for testing the MSE-improvement.     

Outsourcing of Unionized Firms and the Impact of Labor Market Policy Reforms

This paper shows that outsourcing of parts of the workforce in unionized firms leads to wage moderation both in the case of strategic and flexible outsourcing. As long as the share of the outsourced workforce is not too large, this wage‐moderation effect on domestic employment outweighs the direct substitution effect so that domestic employment increases in unionized firms as outsourcing costs fall. With respect to the impact of labor tax reform changes in the wage tax rate, the tax exemption and the unemployment benefit payments affect domestic wage setting in the same way as in the absence of outsourcing. Furthermore, increasing the degree of tax progression by keeping the relative tax burden per worker constant continues to be good for employment. However, except for low outsourcing activities, the impact of these policy measures will become smaller as outsourcing costs fall.     

Stone–Geary preferences in overlapping generations economies under pure exchange: A note

We incorporate Stone–Geary preferences into an overlapping generations economy under pure exchange, and explore stability, indeterminacy, and cycles with positive levels of saving and nonnegative public debt. A stable nontrivial steady state exists for parameter values, for which there does not exist equilibrium in the model with purely logarithmic utility function. We also show the possibility of a period-doubling bifurcation (a two-cycle).     

Is there a Laffer curve between aggregate output and public sector employment?

This paper develops a model of the relationship between public sector employment, total output and aggregate real demand in market prices, where public employment has a positive productivity effect on private output. Public employment crowds out private employment and output because its increase induces higher wages and taxes. The valuation of government output is also taken into account. While public employment affects total output and aggregate real demand in an a priori ambiguous way, numerical simulations suggest that the relationship may be nonlinear; positive, when public sector is “small” and negative, when it is “large”. Using the annual data from 22 OECD countries over the period 1960–1996 and estimating and testing for threshold models and more commonly used specifications with multiplicative interaction terms give support to this nonlinearity hypothesis between public employment and private sector output. First version received: October 1996/Final version received: April 2000     

Green Tax Reform and Competitiveness

This paper studies a revenue-neutral green tax reform that substitutes energy for wage taxes in an open economy with unemployment. As long as the labour tax rate exceeds the energy tax rate, such a reform will increase employment, reduce the domestic firms' unit cost of production and hence increase international competitiveness and output of the economy. The driving force behind these results is the technological substitution process that a green tax reform will bring about. The resulting reduction in unemployment is welfare increasing since energy, which the country has to buy at its true national opportunity cost, is replaced with labour, whose price is above its social opportunity cost.