AGGLOMERATION VERSUS PRODUCT VARIETY: IMPLICATIONS FOR REGIONAL INEQUALITIES*

ABSTRACT We investigate how cross‐country differences in firms' fixed set‐up costs affect the trade‐off between global efficiency and spatial equity. Our analysis reveals that the standard assumption of symmetry in set‐up costs masks the existence of an interesting effect: the range of available varieties depends on the spatial distribution of firms. In such a setting, where the market outcome leads to excessive agglomeration in the symmetric case, a planner may opt for asymmetric set‐up costs and even more agglomeration. We show that the planner will always favor lower set‐up costs in the large country with more agglomeration when the consumer's marginal preference for variety is high, or with less agglomeration when the consumer's marginal preference for variety is low.     

Interpreting the expansion of sea fishing in medieval Europe using stable isotope analysis of archaeological cod bones

Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies.     

Market size,occupational self‐selection,sorting, and income inequality

We develop a monopolistic competition model with heterogeneous agents who self‐select into occupations (entrepreneurs and workers) depending on innate ability. The effect of market size on the equilibrium occupational structure crucially hinges on properties of the lower tier utility function—its scale elasticity and relative love‐for‐variety. When combined with the underlying ability distribution, the share of entrepreneurs and income inequality can increase or decrease with market size. When extended to allow for the endogenous sorting of mobile agents between cities, numerical examples suggest that sorting may increase inequality within and between cities.     

Die (neue) Rolle der Landwirtschaft bei der Umsetzung der EU-Wasserrahmenrichtlinie Erfahrungen aus Nordrhein-Westfalen

Die Wasserrahmenrichtlinie (WRRL) wird im Vergleich zur FFH- und zur Vogelschutzrichtlinie, deren Anforderungen etwa acht Prozent der Landesfl?che von Nordrhein-Westfalen (NRW) betreffen, mit aufzustellenden Bewirtschaftungspl?nen fl?chendeckend ganze Flusseinzugsgebiete erfassen und damit in ihren Auswirkungen für die Landwirtschaft alles Bisherige weit in den Schatten stellen. Insofern hat sich die Landwirtschaft recht frühzeitig in den Umsetzungsprozess der EU-WRRL aktiv eingebracht – angefangen von der Bestandsaufnahme über das Monitoring bis zu den jetzt anlaufenden Ma?nahmenprogrammen.     

Three-dimensional geometry, ore distribution and time-integrated mass transfer through the quartz–tourmaline–gold vein network of the Sigma deposit (Abitibi belt, Canada)

We present a reconstruction of the three‐dimensional (3D) geometry and gold grade distribution of shear zone‐hosted, Au‐mineralized, quartz–tourmaline veins of the Sigma deposit (Abitibi belt). Host shears and veins form a network of anastomosing, steeply dipping structures associated with smaller subhorizontal extensional veins. Our reconstruction has been carried out using the exceptionally large geological database of the mine. From this database, we extracted the geometric position, thickness and gold grades of geometrically best‐defined steep veins contained in a representative subvolume of the deposit. These data allowed the 3D representation of 53 veins, which have been constructed by fitting surfaces through the geometrical data and by contouring thickness and gold grade. The geometry of the network is mainly characterized by: (i) a few large segmented veins, with sinuous and helicoidal shape, and typical vertical dimension of >100 m; (ii) a large number of smaller vertical veins, some of which splay off the steep veins with high dip angles; (iii) subhorizontal extension veins (joints) located at, or close to, the tips of steep veins. The absolute thickness of the vertically short veins is the same as that of the large veins, suggesting that they formed simultaneously, but only a few of them interconnect to form vertically continuous bodies. Patchy, vertically elongated zones of high dilation are present in the large veins, and are poorly correlated with Au‐rich zones. They presumably represent former high‐permeability zones of the network. The highest gold grades occur at the interconnections between the large veins and small splays or subhorizontal joints. This indicates the important role of vein interconnection for fluid flow and gold precipitation within the network. Combining the calculation of the volume of the network with the estimation of tourmaline abundance in the veins, we calculate that 2.1 × 10⁶ m³ of tourmaline and 3.2 × 10⁶ m³ of quartz precipitated during Au deposition.