Monopoly and optimal nonlinear pricing: the case of route monopolies and heteregeneous demand in the air transport market

This paper explores the robustness of the one-dimensional screening model with respect to increasing the number of instruments and the number of characteristics. We study a case of nonlinear pricing (2 instruments (2 routes on which the airline provides customers with services), 2 characteristics (demand of services on these routes) and two values per characteristic (a low or a high demand of services on these routes)) and we show that none of the conclusions of the one-dimensional analysis remain valid. In particular, upward incentive compatibility constraint may be binding at the optimum. As a consequence, they may be distortion at the top of the distribution. In addition to this, we show that the optimal solution often requires bundling, while it is sometimes optimal for the monopolist to produce only one good or to exclude some buyers from the market. This means that the monopolist cannot fully apply his monopoly power and is better off selling two goods independently. We define all possible solutions in the case of a quadratic cost function for a uniform distribution of agent types and demonstrate that the range of services proposed by an airline is often larger than the corresponding range in demand.     

The Bases of Compromise in the Workplace: A Theoretical Framework

Schemes for workplace participation have long been promoted and vilified. Such conflicting views have been brought into sharp focus by the highly variable results of such practices as teamwork. Yet a theoretical framework to grasp workplace co‐operation is lacking. This paper develops a framework on the basis of theory and a review of a wide range of empirical studies. Capital and labour each have two sets of ‘concerns’: over ‘control’ of the workplace and the longer term ‘development’ of the productive forces. Cross‐classifying these concerns produces a matrix of patterns of workplace relations. Each cell of the matrix represents a different combination of the interests of capital and labour. The matrix can be used to map participation schemes so as to capture their varying features. The next task, pursued elsewhere, is to identify the conditions leading to locations in different cells of the matrix.     

MEASURING MULTIDIMENSIONAL POVERTY: AN EMPIRICAL COMPARISON OF VARIOUS APPROACHES

This paper makes a systematic comparison of four approaches to multidimensional poverty analysis based respectively on the theory of fuzzy sets, information theory, efficiency analysis and axiomatic derivations of poverty indices. The database was the 1995 Israeli Census that provided information on the ownership of various durable goods. There appears to be a fair degree of agreement between the various multidimensional poverty indices concerning the identification of the poor households. The four approaches have also shown that poverty decreases with the schooling level of the head of the household, first decreases and then increases with his/her age and with the size of the household. Poverty is higher when the head of the household is single and lower when he/she is married, lowest when the head of the household is Jewish and highest when he/she is Muslim. Poverty is also higher among households whose head immigrated in recent years, does not work or lives in Jerusalem. These observations were made on the basis of logit regressions. This impact on poverty of many of the variables is not very different from the one that is observed when poverty measurement is based only on the income or the total expenditures of the households.     

Bayesian regression analysis using poly-t densities

Poly-t densities are defined by the property that their kernel is a product, or ratio of products, of Student-t kernels. These multivariate densities arise as Bayesian posterior densities for regression coefficients, under a surprising variety of specifications for the prior density and the data generating process. Although no analytical expression exists for the integrating constant and moments of these densities, these parameters are obtained through numerical integration in a number of dimensions given by the number of Student-t kernels in the numerator, minus one. The paper reviews how poly-t densities arise in regression analysis, and summarizes the results obtained for a number of models.     

The firm's investment and employment policy through a business cycle

The paper studies with the help of a model the investment and employment policy through a business cycle for a firm which maximizes its discounted income and assumes that the forecasts are perfectly correct. In addition to investment and wages costs, the firm has to bear recruitment and firing costs; it has at its disposal four control variables: the selling price, the recruitment rate, the firing rate and the investment rate. The firm's strategy appears to be generally a sequence of elementary policies. This sequence highly depends on the relative values of parameters like the rate of depreciation of equipment, the natural rate of decrease of employment, the ratio of the unit recruitment and firing cost with respect to the wage rate, the rate of decrease of demand during recession. The results obtained are, on the whole, quite consistent with the behaviours which have been observed in the last years, and explain some of the features of recessions.     

On supply-constrained equilibria

The paper gives sufficient conditions for the existence of an equilibrium with price rigidities and quantity rationing where: (i) demand is never rationed; (ii) net trades of an a priori chosen numeraire are never rationed; and (iii) supply is rationed only when relative prices are downward rigid.