Alonso (1978) and Bikker (1982) independently introducé the Three Component (3-C) model. This is a model to explain and predict flows between origins and destinations. It generalizes many existing models, such as the gravity model. This generality is attained through so-called "systemic variables". Unfortunately, the interpretation of these variables, and hence that of the 3-C model, have remai...

We analyze the anonymous communication patterns of 2.5 million customers of a Belgian mobile phone operator. Grouping customers by billing address, we build a social network of cities that consists of communications between 571 cities in Belgium. We show that inter-city communication intensity is characterized by a gravity model: the communication intensity between two cities is proportional to...

Pacific economies are confronted with several structural constraints that limit their economic growth, most importantly their small size and remoteness from major world markets. In this paper we study the importance of transport connectivity for Pacific economies when participating in the world economy. The paper first describes the evolution of trade flows of the Pacific economies over the las...

This paper assesses the determinants of trade in services using a gravity model, with particular attention given to the role of barriers to services trade. Initially, the application of the gravity equation to services trade is examined. A variety of econometric estimators are tested and the Hausman-Taylor model is found to be the best estimator. The gravity model fits services trade flows in a...

T.N. Srinivasan and Vani Archana INTRODUCTION The standard models of international trade such as the Ricardian, Hecksher-OhlinSamulelson (HOS) and specific factor models focus on explaining the commodity patterns of trade between countries and their determinants primarily comparative advantage. Constant returns to scale in production are assumed to prevail so that the structure of production in...

Steady and unsteady two-dimensional free surface flows subjected to one or multiple disturbances are considered. Flow configurations involving either a single fluid or two layers of fluid of different but constant densities, are examined. Both the effects of gravity and surface tension are included. Fully nonlinear boundary integral equation techniques based on Cauchy’s integral formula are use...

This paper deals with a theoretical investigation of heat and mass transfer with thermal radiation analysis on hydromagnetic peristaltic Prandtl fluid model with porous medium through an asymmetric tapered vertical channel under the influence of gravity field. Analytical results are found for the velocity, pressure gradient, pressure rise, frictional force, temperature and concentration. The in...