A Schumpeterian model of growth and inequality.

This paper contributes to the analysis of the effects of demand structure on longterm growth. Introducing non-homothetic preferences in an otherwise standard quality- model, we first show that disparities in purchasing power generate positive R&D investment by quality leaders. This result is obtained with complete equal treatment in the R&D field between the incumbent patentholder and the challengers as well as without any concavity in the R&D cost function: in our framework, the incentive for a leader to invest in R&D stems from the possibility for an incumbent having innovated twice in a row to efficiently discriminate between rich and poor consumers displaying differences in their willingness to pay for quality. We hence exemplify a so far overlooked demand-driven rationale for innovation by incumbents. We then move to analyzing the impact of inequalities on long-term growth in our quality-ladder framework, and find that a lower level of wealth disparities always leads to an increase in the long-run growth rate. Finally, we show that beyond this negative impact on growth, inequalities also influence the allocation of the overall R&D effort between incumbents and challengers: a higher level of inequalities will in most cases lead to a bigger share of the overall R&D investment to be carried out by quality leaders.Growth, Innovation, Income inequalities.

Trade in quality and income distribution: an analysis of the enlarged EU market.

This paper contributes to the understanding of the determinants of country-level comparative advantages in terms of quality. More precisely, while the literature has mainly focused so far on supply-side determinants of such comparative advantages, we investigate both theoretically and empirically the role played by income distribution (average income and level of inequalities) of a country on the quality of its exports. Doing so, we provide new insights on the existence of demand-based determinants of the quality content of a country’s exports, in line with the Linder (1961) hypothesis, claiming that firms produce and export goods suited to the specific tastes of their local consumers. We build a model with economies of scale where non-homothetic preferences and within-country income differences determine the quality composition of production and exports. Having neutralized any supply-side comparative advantage, we show that richer countries produce and export higher quality goods, while the level of inequalities has an heterogenous impact, positively affecting the quality content of exports for rich enough countries only. We then corroborate our theoretical predictions on bilateral trade data for the enlarged European Union (EU), an integrated market displaying significant heterogeneity in terms of both average income and within-country inequalities of its members. Furthermore, we are able to show that in terms of magnitude of the effects, inequalities are a second-order demand-based determinant of the quality of exports as compared to average income.Product quality, Income distribution, Trade, Economies of scale, European Union.

Beyond the Arrow effect: a Schumpeterian theory of multi-quality firms *

This paper introduces multi-quality firms within a Schumpeterian framework. Featuring non-homothetic preferences and income disparities in an otherwise standard quality-ladder model, we show that the resulting differences in the willingness to pay for quality among consumers generate both positive investments in R&D by industry leaders and positive market shares for more than one quality, hence allowing for the emergence of multi-product firms within a vertical innovation framework. This positive investment in R&D by incumbents is obtained with complete equal treatment in the R&D field between the incumbent patentholder and the challengers: in our framework , the incentive for a leader to invest in R&D stems from the possibility for an incumbent having innovated twice in a row to efficiently discriminate between rich and poor consumers displaying differences in their willingness to pay for quality. We hence exemplify a so far overlooked demand-driven rationale for innovation by incumbents. Such a framework also makes it possible to analyze the impact of inequality both on long-term growth and on the allocation of R&D activities between challengers and incumbents. We find that an increase in the income gap positively impacts an econ-omy's growth rate, partly shifting R&D activities from challengers to incumbents. On the other hand, a greater income concentration is detrimental for growth, diminishing both the incumbents' and the challengers' R&D activities

How do epidemics induce behavioral changes?

This paper develops a theory of optimal fertility behavior under mortality shocks. In a 3- periods OLG model, young adults determine their optimal fertility, labor supply and life-cycle consumption with both exogenous child and adult mortality risks. For fixed prices (real wages and interest rate), it is shown that both child and adult one-period mortality shocks raise fertility due to insurance and life-cycle mechanisms respectively. In general equilibrium, adult mortality shocks give rise to price effects (notably through rising wages) lowering fertility, in contrast to child mortality shocks. We complement our theory with an empirical analysis on a sample of 39 Sub-Saharan African countries over the 1980-2004 period, checking for the overall effects of the adult and child mortality channels on optimal fertility behavior. We find child mortality to exert a robust, positive impact on fertility, whereas the reverse is true for adult mortality. We further find this negative effect on fertility of a rise in adult mortality to dominate in the long-term the positive effect on demand for children resulting from an increase in child mortality.fertility, mortality, epidemics, HIV

How do epidemics induce behavioral changes ?

This paper develops a theory of optimal fertility behavior under mortality schocks. In a 3-periods OLG model, young adults determine their optimal fertility, labor supply and life-cycle consumption with both exogenous child and adult mortality risks. For fixed prices (real wages and interest rate), it is shown that both child and adult one-period mortality shocks raise fertility due to insurance and life-cycle mechanisms respectively. In general equilibrium, adult mortality shocks give risse to price effects (notably through rising wages) lowering fertility, in contrast to child mortality shocks. We complement our theory with an empirical analysis on a sample of 39 Sub-Saharan African countries over the 1980-2004 period, checking for the overall effects of the adult and child mortality channels on optimal fertility behavior. We find child mortality to exert a robust, positive impact on fertility, whereas the reverse is ture for adult mortality. We further find this negative effect fertility of a rise in adult mortality to dominate in the long-term the positive effect on demand for children resulting from an increase in child mortality.fertility, mortality, epidemics, HIV

How do epidemics induce behavioral changes?

This paper is concerned with the impact of epidemics on economic behavior, and in particular on fertility and schooling. Special attention is paid to the fertility eect, which has been at the heart of a recent controversy around the AIDS crisis. An illustrative model is proposed where agents choose labor supply, life-cycle consumption and the number of children. We show that the optimal response in terms of fertility and labor supply to an epidemic shock depends on the relative strength of two forces at work, deriving from: (i) the induced decrease in the survival probability, and (ii) the impact of epidemics on wages. A comprehensive empirical study is then proposed to disentangle the latter eects in the HIV/AIDS and malaria cases. Using data from 69 developing countries over the period 1980-2004, we nd that HIV/AIDS has a robust negative eect on fertility and a robust positive eect on education, while opposite results are found in the case of malaria. We argue that this discrepancy can be attributed to a sizeable wage eect in the AIDS case while such an eect is rather negligible under malaria at least in the short term, as higher malaria prevalence depresses wages in the long term.

Variable Markups in the Long-Run: A Generalization of Preferences in Growth Models

This paper introduces variable mark-ups in a horizontal-differentiation growth model by considering a larger class of preferences that nests the classic “CES” specification usually present in the workhorse love-for-variety models. Our first result is to obtain a generalized characterization of the Euler condition for this broader class of utility functions: in our model, the Euler rule features a supplementary term aiming at compensating the consumer for variations in the preference for variety along the consumption level. We are then also able to demonstrate that in our generalized framework, the economy’s balanced growth path displays both endogenous markups and a strictly positive growth rate of the number of available varieties (being the engine of growth). Finally, we show that under endogenous markups, the economy’s growth rate and firms’ market power can display a negative correlation, as opposed to the standard result obtained in the CES framework

Perspectives économiques 2007-2008

D’après les indicateurs conjoncturels récents, l’état actuel de l’économie belge demeure bien orienté. Les perspectives économiques pour les 18 prochains mois sont positives, avec une croissance que nous prévoyons à 2,8 % en 2007 et 2,5 % en 2008.

Perspectives économiques 2009

En raison de l’aggravation de la crise financière, du recul de l’activité économique dans de nombreux pays avancés, et d’une dégradation particulièrement sévère des anticipations des ménages et des entreprises, les perspectives macroéconomiques pour la Belgique se sont fortement détériorées au cours des derniers mois. Par rapport à notre projection d’octobre 2008, le taux de croissance annuel moyen du PIB belge prévu pour 2009 a été très fortement révisé en baisse. Il s’établit à - 0,9 %, par rapport à la prévision d’une croissance positive de 0,8 % en octobre dernier.

Perspectives économiques 2010 - 2011

Les développements économiques récents confirment la reprise de l'économie mondiale et le redressement de l'économie belge. Malgré les turbulences financières des derniers mois, l'évolution attendue de la situation économique sur la période de projection reste favorable. Les risques sont néanmoins élevés. En 2010, le PIB belge devrait croître de 1,3 %. Sa croissance devrait se relever à nouveau en 2011, pour atteindre 2,0 %.