Modelling unobserved heterogeneity in distribution - Finite mixtures of the Johnson family of distributions [31/08/2017]
This paper proposes a new model to account for unobserved heterogeneity in empirical modelling. The model extends the well-known Finite Mixture (or Latent Class) Model by using the Johnson family of distributions for the component densities. Due to the great variety of distributional shapes that can be assumed by the Johnson family, the method does not impose the usual a priori assumptions regarding the type of densities that are mixed.Working Paper 14-17
This Working Paper presents the projection methodology for internal migration, which is integrated from 2016 in the population projections published by the Federal Planning Bureau and Statistics Belgium. The methodology is based on migration intensity between districts, rather than on emigration rates from one district to another. With migration intensity, not only is the population of the departure district taken into account (population at risk of moving) but also the population of the destination district (as a proxy for attractiveness). The short-term evolution of migration intensity is in line with the most recent trends observed in a series of preferential migration flows between districts. In the long term, migration intensity is assumed to be constant.Working Paper 10-16
Drivers of wholesale electricity prices in a small, open economy - Some evidence from the nuclear restart in Belgium [12/10/2016]
In this paper, the impact of a nuclear downtime and subsequent restart on wholesale electricity prices on the Belgian power exchange is investigated by means of a dual methodology. First, publicly available market data is used to construct a stable statistical model that is deployed to examine the effect of nuclear power generation variations on market price outcomes. Quantifying this phenomenon, also called the merit-order effect, with the aid of econometric methods translates into an esti-mated price decrease of around 10 €/MWh for a nuclear capacity hike of 2.5 GW. The importance and impact of the openness of the Belgian market, that is, its strong reliance on cross-border energy exchanges is highlighted. Next to this empirical evidence, the optimisation tool Crystal Super Grid is used to assess the impact of the resumed availability of the nuclear reactors on several indicators characterising the Belgian and European power landscape. A positive effect on overall welfare, consumer surplus and CO2 emissions can be noticed. As regards prices, this analysis confirms the negative merit-order effect which is calculated to equal, on average over a year, 3.8 €/MWh. Nevertheless, temporary hourly excesses of 30 €/MWh can occur. The paper then describes the possible causes of divergence between the two approaches.
Our findings have important policy implications as they demonstrate the need to take the downward influence of prolonged nuclear power generation on wholesale prices into consideration when revising the (timetable in the) nuclear phase-out law since it may have a delaying effect on the compulsory energy transition towards a low-carbon economy.Working Paper 09-16
This Working Paper presents the methodological progress made in projecting international migration. The new methodology is notably based on an analysis of migration flows per nationality and on statistics on reasons for migrating, in order to assess whether economic variables constitute relevant determinants of migration. If they do, the impact of economic determinants on immigration is estimated using econometric methods. The methodology also takes into account the increasing globalization and mobility as well as the expected growth of the global population which boost international migration flows (immigration and emigration). Finally, it grants more stability to the long-term migration projections and, therefore, to the population projections; the annual revisions of long-term migration will be less dependent on the short-term evolution of migration flows.Working Paper 02-15
This paper presents an allocation model of Belgian household consumption over 23 categories of goods and services. We have formulated and estimated an extension of the classic Almost Ideal Demand System. The original model has been modified by introducing a dynamic adjustment mechanism and by the inclusion of demographic variables. These capture shifts in consumption patterns related to the changing age composition of the population. The paper is an extension of earlier work (Willemé, 2008), in particular with respect to the number and composition of the consumption categories considered.Working Paper 15-12