Monitoring data in R with the lumberjack package

Monitoring data while it is processed and transformed can yield detailed insight into the dynamics of a (running) production system. The lumberjack package is a lightweight package allowing users to follow how an R object is transformed as it is manipulated by R code. The package abstracts all logging code from the user, who only needs to specify which objects are logged and what information should be logged. A few default loggers are included with the package but the package is extensible through user-defined logger objects.Comment: Accepted for publication in the Journal of Statistical Softwar

The Oosterweel junction revisited.

This paper assesses the Oosterweel junction, a new tunnel under the river Scheldt, that aims to alleviate the congestion on the existing tunnels and on the Ring of Antwerp. The paper uses data from existing studies of the same project to calibrate a simple network model (MOLINO-II). The model is then used to compare alternatives with and without the new tunnel. The alternatives include different combinations of tolls and bans on trucks. The study concludes that the first priority is not to build new capacity but to remove the pricing distortions on the existing capacity. The alternatives that include a pricing reform are the only ones that generate a positive net benefit, almost all scenarios that include the new tunnel have a negative net benefit.

The European road pricing game: how to enforce optimal pricing in high-transit countries under asymmetric information.

A federal government tries to force local governments to implement welfare optimal tolling and investment. Welfare optimal tolling requires charging for marginal external costs. Local governments have an incentive to charge more than the marginal social cost whenever there is transit traffic. We analyse the pricing and investment issue in an asymmetric information setting where the local governments have better information than the federal government. The case of air pollution and of congestion are discussed.

Transport Infrastructure Investment and Demand Uncertainty

In transportation planning there can be long lead times to adapt capacity. This paper addresses two questions. First, in a one mode world (say rail or road), what is the optimal capacity choice when faced with uncertain demand, long lead times and congestion. Using a simple analytical model it is shown that when demand is inelastic, it is socially optimal to invest more than if only the expected level of demand is taken into account. In this case it may be beneficial to overinvest in capacity because congestion costs are a convex function of relative use. This result holds with or without optimal tolling. The second question deals with two competing modes and where only one mode has long lead times for capacity while the other has flexible capacity. This is typical for the competition between High Speed Rail and air for the medium distance trips (500 to 1000 km), or for the competition between inland waterways and trucks for freight. We find that overinvestment is less justified because the substitute mode can more easily absorb the high demand outcomes.transport infrastructure, uncertainty, investments

Transport infrastructure investment and demand uncertainty.

In transportation planning there can be long lead times to adapt capacity. This paper addresses two questions. First, in a one mode world (say rail or road), what is the optimal capacity choice when faced with uncertain demand, long lead times and congestion. Using a simple analytical model it is shown that when demand is inelastic, it is socially optimal to invest more than if only the expected level of demand is taken into account. In this case it may be beneficial to overinvest in capacity because congestion costs are a convex function of relative use. This result holds with or without optimal tolling. The second question deals with two competing modes and where only one mode has long lead times for capacity while the other has flexible capacity. This is typical for the competition between High Speed Rail and air for the medium distance trips (500 to 1000 km), or for the competition between inland waterways and trucks for freight. We find that overinvestment is less justified because the substitute mode can more easily absorb the high demand outcomes.Transport infrastructure; Uncertainty; Investments;

The EU's Association Agreements and DCFTAs with Ukraine, Moldova and Georgia: A Comparative Study. CEPS Special Report, 24 June 2017

This paper compares the three Association Agreements (AAs) and Deep and Comprehensive Free Trade Areas (DCFTAs) that the EU has concluded with Ukraine, Moldova and Georgia. In particular, it explores the main differences in the ‘political’ and trade-related chapters and the provisions on legislative approximation. Whereas the scope and contents of these sets of agreements are very similar, some specific differences can be identified in view of the different political and economic priorities of the EU’s partner countries

The Dilemma of the EU’s Future Trade Relations with Western Sahara: Caught between strategic interests and international law? CEPS Commentary 20 April 2018

Following the Court of Justice’s Polisario rulings, the EU is facing thorny legal and political challenges to include Western Sahara in its trade agreements with Morocco

The Dutch Referendum on the EU-Ukraine Association Agreement: Legal options for navigating a tricky and awkward situation. CEPS Commentary, 8 April 2016

In an advisory referendum held in the Netherlands on April 6th, over 61% of the voters rejected the ratification of the Association Agreement (AA) between the EU and Ukraine. If the Dutch government were to act on the outcome of the referendum, which had a low turnout of 32%, an unprecedented situation would emerge in which an EU international agreement cannot enter into force because a member state is not in a position to ratify it. Although the political character of this referendum and the Dutch Advisory Referendum Act (DRA) and the geopolitical implications of the AA itself have already been the subject of heated discussions in the Netherlands and beyond, the legal implications of this referendum remain unclear