Reconstruction and visualisation of melt topology in veined microdioritic enclaves

A number of xenocrystic microdioritic enclaves within the Ross of Mull Granite contain narrow veins of monzonitic material that have formed through the selective partial fusion of granitic magma mechanically incorporated into the microdiorite magma. Field evidence suggests that, as melting of the granitic material ensued, a monzonitic melt formed and exfiltrated from the surrounding microdioritic matrix resulting in Saffman–Taylor instabilities and the development of viscous fingering phenomena. The monzonitic melt network is now preserved as monzonitic veins. Mechanical serial sectioning through a representative veined microdioritic enclave shows that: (a) the topology of the veins is complex but crudely polyhedral, (b) there is porosity (monzonitic melt fraction) variation throughout the length of the veined enclave and (c) that the monzonitic veins are interconnected in three dimensions. Using image analysis software, the total porosity of individual veined enclave sections has been estimated, along with the variation in porosity with depth. Three dimensional rendering and animation software has been used to reconstruct and visualise the monzonitic melt network using Apple QuickTime? software. The above method provides a cheap and powerful way of visualising remnant macroscopic transport properties (such as connectivity and melt topology) in partially molten igneous rocks.     

Current-Account Reversals in Developing Countries: The Role of Fundamentals

This paper studies episodes of current-account reversal in developing countries (DCs) in the period 1965–1994. First, a number of persistent shifts (reversals) in the current-account balance dynamics are identified by structural break and segmented trend tests; then, the relationship between these reversals and a set of fundamentals suggested by the intertemporal approach to the current account is investigated in a panel-data set-up. We find that fundamentals play a different role in episodes of persistent deterioration or improvement of the current-account balance in DCs.     

Preemption contests between groups

We consider a preemption game between competing groups; firms lobbying individually for their groups' interests provide an empirical example. Among symmetric groups, the first firm to take action bears an (unobserved) cost and wins the prize on behalf of its group. In equilibrium, the firm with the lowest cost takes action, but with delay. More competition and a smaller ratio of costs to benefits reduce delay. Firms in larger groups wait longer, but group action can occur earlier, as the probability of a low-cost firm is higher. Asymmetries in group size or strength of externalities also matter.     

What do bank acquirers want? Evidence from worldwide bank M&A targets

What drives bankers to create larger and larger, often multinational banking groups? In this paper we investigate whether the targets in cross-border bank M&As are materially different from those banks targeted in domestic M&A deals. The main message of this paper is that, with few exceptions, domestic and foreign investors target similar banks. In particular, and contrary to what one might expect, bank size does not have a different effect on the probability of being a domestic or a cross-border target, instead it has a positive and highly significant effect in both cases. We find that the main differences between national and international M&As are the characteristics of the countries where the banks operate.     

Multiple equilibria in a cash-in-advance two-sector economy

We consider a two-sector infinite horizon economy with a fractional cash-in-advance constraint on consumption expenditures. This formulation allows us to consider a steady-state velocity of money that is strictly greater than one and, therefore, provides a more plausible framework than the standard formulation in which all the consumption purchases are paid cash. We prove that the steady state is bound to be indeterminate and multiple equilibria occur when the share of the liquidity constraint is low enough and that a capital-intensive investment good or a strongly capital-intensive consumption good improve considerably the scope for indeterminacy. As a consequence, we show that without any restriction on the elasticity of intertemporal substitution in consumption, multiple equilibria might occur if the velocity of money is greater than a critical bound that is compatible with empirical estimates.     

Powerless: gains from trade when firm productivity is not Pareto distributed

Most trade models featuring heterogeneous firms assume a Pareto productivity distribution, on the basis that it provides a reasonable representation of the data and because of its analytical tractability. However, recent work shows that the characteristics of the productivity distribution crucially affect the estimated gains from trade. This paper thoroughly compares the gains from trade obtained under three different productivity distributions (Pareto, lognormal, and Weibull) and investigates their policy implications. We find that both the magnitude of the welfare gains and the relative importance of the fixed versus variable trade costs change significantly. Hence, relying blindly on a single distribution is dangerous when performing trade policy analysis.     

Competition and Regulation in Network Industries: Not an Easy Balance to Strike. Comments on Koski and Kretschmer*

Network industries present several counterintuitive aspects. This peculiarity has attracted particular attention among policymakers, but public intervention has not always been irreproachable. A continuously improving appraisal of network industries tends to allow a better informed policy action and a good balance between otherwise potentially competing policies (competition policy and sector-specific regulation in the first place, but also innovation and standardization policies).     

New Tools to Foster Corporate Socially Responsible Behavior

According to the Green Paper presented by the European Commission in July 2001, corporate social responsibility (CSR) is “a concept whereby companies integrate social and environmental concerns in their business operations and in their interaction with their stakeholders on a voluntary basis” (Commission of the European Communities, 2001b, p. 6). On this basis, in 2002, the Italian Government, and especially the Italian Ministry of Welfare, launched an initiative called CSR-SC (social commitment) in order to foster the proactive social role of Italian enterprises, with great attention on SME involvement. The technical partner of the Italian Ministry of Welfare for this initiative is Bocconi University. The goal of this contribution is to present the main results of CSR–SC research project developed by Bocconi University. The paper provides a detailed picture of the general scheme designed to carry out the research project and a review of the different methodologies used to support the solutions proposed.     

Measures of economies with an arbitrarily large number of equilibria

Balasko (1978) shows that in a compact subset of the space of economies, not too many economies can have too many equilibria. We extend Balasko’s result to the whole set of economies for a suitable measure. We show that the measure of economies with a large number of equilibria approaches zero as this number tends to infinity. An analogous result in the infinite‐dimensional setting is also established.