Geographical disadvantage - a Heckscher-Ohlin-von Thunen model of international specialization

The combination of distance, poor infrastructure, and being landlocked by neighbors with poor infrastructure, can make transport costs many times higher for some developing countries than for most others. Drawing on two traditions of economic modeling --Heckscher-Ohlin trade theory and von Thunen's work on the"isolated state"- the authors analyze the trade and production patterns of countries located at varying distances from an economic center. Predicting a country's production and trade pattern requires a knowledge of the country's location, its factor endowment, and the factor and transport intensities of goods. The authors define transport intensity and show how location and transport intensity should be combined with factor abundance and factor intensity, in determining trade flows. A theory based on only one set of those variables, such as factor abundance, will systematically make incorrect predictions. They report that geography and endowments interact in such a way that the world divides up into economic zones with different trade patterns. Countries close to the economic center may specialize in transport-intensive activities; countries further out become diversified, producing, and sometimes trading more goods; countries still further out may become import-substituting (replacing some of their imports from the center with local production); in the extreme, regions become autarkic. More remote locations have lower real incomes. Globalization changes the terms of trade, improving the welfare of regions further out from economic centers, though reducing the welfare of closer regions. Where will a new activity, such as assembly of a new product, locate? Remote locations are disadvantaged if the product has high transport intensity (perhaps because of heavy requirements for intermediate inputs). But the costs of remoteness are already incorporated into the factor prices of those regions, which makes them more attractive. Which location is chosen depends, therefore, on how existing activities compare with the new activity in transport intensity and factor intensity.Transport Economics Policy&Planning,Environmental Economics&Policies,Payment Systems&Infrastructure,Economic Theory&Research,Labor Policies,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Banks&Banking Reform,Transport Economics Policy&Planning,Economic Theory&Research,Environmental Economics&Policies

Infrastructure, geographical disadvantage, and transport costs

The authors use three different data sets to investigate how transport depends on geography and infrastructure. Landlocked countries have high transport costs, which can be substantially reduced by improving the quality of their infrastructure and that of transit countries. Analysis of bilateral trade data confirms the importance of infrastructure. The authors estimate the elasticity of trade flows with regard to transport costs to be high, at about -2.5. This means that: 1) The median landlocked country has only 30 percent of the trade volume of the median coastal economy. 2) Halving transport costs increases the volume of trade by a factor of five. 3) Improving infrastructure from the 75th to the 50th percentile increases trade by 50 percent. Using their results and a basic gravity model to study Sub-Saharan African trade, both internally and with the rest of the world, the authors find that infrastructure problems largely explain the relatively low levels of African trade.Banks&Banking Reform,Economic Theory&Research,Common Carriers Industry,Transport Economics Policy&Planning,Municipal Financial Management,Municipal Financial Management,Common Carriers Industry,Transport Economics Policy&Planning,Economic Theory&Research,Banks&Banking Reform

K-theory for Cuntz-Krieger algebras arising from real quadratic maps

We compute the $K$-groups for the Cuntz-Krieger algebras $\mathcal{O}_{A_{\mathcal{K}(f_{\mu})}}$, where $A_{\mathcal{K}(f_{\mu})}$ is the Markov transition matrix arising from the \textit{kneading sequence }$\mathcal{K} (f_{\mu})$ of the one-parameter family of real quadratic maps $f_{\mu}$.Comment: 8 page

Analytic theory of fiber-optic Raman polarizers

The Raman polarizer is a Raman amplifier which not only amplifies but also re-polarizes light. We propose a relatively simple and analytically tractable model - the ideal Raman polarizer, for describing the operation of this device. The model efficiently determines key device parameters such as the degree of polarization, the alignment parameter, the gain and the RIN variance

Colour Fields Computed in SU(3) Lattice QCD for the Static Tetraquark System

The colour fields created by the static tetraquark system are computed in quenched SU(3) lattice QCD, in a 24^3 x 48 lattice at beta=6.2 corresponding to a lattice spacing a=0.07261(85) fm. We find that the tetraquark colour fields are well described by a double-Y, or butterfly, shaped flux tube. The two flux tube junction points are compatible with Fermat points minimizing the total flux tube length. We also compare the diquark-diantiquark central flux tube profile in the tetraquark with the quark-antiquark fundamental flux tube profile in the meson, and they match, thus showing that the tetraquark flux tubes are composed of fundamental flux tubes.Comment: 5 pages, 7 figures, 0 tables, one reference added, work done partly under the PT-LQCD Collaboratio