Jorge Diaz Lanchas (p), Carlos LLano-Verduras, José L. Zofío

Patrick Niérat

Empirical evidence has been lacking to explain trade agglomerations over short distances. Starting
with a novel micro-database of road freight shipments within Spain for the period 2003-2007, we
break down city (municipal) trade flows into the extensive and intensive margins and assess trade
frictions and trade concentration relying on a unique generalized transport cost measure and three
internal borders, NUTS-5 (municipal), NUTS-3 (provincial) and NUTS-2 (regional). We discover
a stark accumulation of trade flows up to a transport cost value of 189Euros (approx. 170km) and
conclude that this high density is due not to administrative borders effects but to significant changes
in the trade-to-transport costs relationship. To support this hypothesis, we propose and conduct
an endogenous Chow test to identify significant thresholds at which trade flows change structurally
with distance. These breakpoints allow us to split the sample when controlling for internal borders,
and to define trade market areas corresponding to specific transport costs values that consistently
reveal an urban hierarchy of cities. The results provide clear evidence to corroborate the predictions
of central place theory.

Damiaan Persyn (p), Jorge Diaz Lanchas , Javier Barbero Jimenez

Patrick Niérat

Transport costs are a crucial element of any spatial economic model. Surprisingly, good transport cost estimates at a detailed spatial level for the EU are not readily available. In this paper we address this issue by estimating a novel dataset of road freight transport costs for goods for the EU regions at the NUTS 2 level. In the spirit of the generalized transport cost (GTC) concept, we calculate the composite cost related to distance and time for the optimal route of a representative truck. We consider routes between large random samples of centroids drawn from a 1kmx1km population density grid. These transport costs are averaged to obtain an origin-destination cost matrix (in euros) at the region-pair level. The sampling approach also allows calculating the average transport cost within the regions. We separately report the corresponding iceberg transport costs for each pair of European regions, since this is the form of input required by many economic models. We also consider the effect of changes in the components of the GTC in order to evaluate transport policies. We set up a transport policy tool to assess the impact of road-transport infrastructure investment in a region by considering upgrading roads to highways. We apply this tool to study transport infrastructure investment through the European Cohesion Policy program 2014-2020.

David Guerrero (p), Jean-Claude Thill (p)

Patrick Niérat

Freight route decisions such port or modal choice are largely pre-constrained by commercial and logistics constraints of shippers and consignees. Policy makers aiming to favor the use of certain transport modes or ports, are often exclusively focused on transport issues and tend to neglect this issue. This paper demonstrates that logistics choices made by shippers and consignees, such the shipment size, the involvement of freight forwarders, or the ways in which different goods are consolidated, largely contribute to subsequent routing decisions. The impacts of these logistics characteristics on the routing behavior are measured for a sample of deep-sea shipments.
A discrete choice model is used to analyze the geographical distribution of maritime shipments of wine and spirits between French shippers, West-European ports and US ports. The routing choice is estimated on the basis of a combination of factors pertaining to transport (i.e. distance to the port, port efficiency…), production (i.e. shipper’s size, shipper’s main activity) and logistics (size of the shipment, if a freight forwarder is involved or not, if the container contains products from one or several regions…).
To estimate the choice model, we use data that describe shipments of wine and spirits exported from France to the United States in October 2006. The choice of a single type of cargo means that comparisons between flows of different origin-destinations can be reasonably made, avoiding the problem of heterogeneity of shippers. Moreover, the method used helps the identification of actors involved in the supply chain and their locations. Indeed, when analyzing freight flows the problem of shipper’s location is an important one, since the HQ of firms or warehouses are often declared as the first origin of final destination of cargo. To overcome this issue, keywords related to the geographical designation of origin (i.e. Cognac, Sancerre) are used to precisely describe the origins of the cargo contained in containers.
Our first results indicate that routing decisions of French wines and spirits heavily rely on a few large freight forwarders and shippers. Although the port of Le Havre is largely used by small shippers, Antwerp, Marseilles and Rotterdam play non-negligible roles as well for specific wine regions and shippers. When the shipper is equidistant to different ports, shipper’s size, or the ways in which importers or freight forwarders consolidate wines and spirits from different regions affect the choice of the port.