Finite Mechanical Proxies for a Class of Reducible Continuum Systems

We present the exact finite reduction of a class of nonlinearly perturbed wave equations, based on the Amann-Conley-Zehnder paradigm. By solving an inverse eigenvalue problem, we establish an equivalence between the spectral finite description derived from A-C-Z and a discrete mechanical model, a well definite finite spring-mass system. By doing so, we decrypt the abstract information encoded in the finite reduction and obtain a physically sound proxy for the continuous problem.Comment: 15 pages, 3 figure

The role of guarantees in bank lending

Guarantees play an important role in debt contracts. They alter the risk for the lender, transform borrowersÂ’ incentives and, possibly, modify the equilibrium allocation of financial resources. This paper studies the role of guarantees on bank loans, using a sample of over 50,000 individual lines of credit granted by Italian banks. Two empirical models are used. The first directly verifies the relationship between ex-ante publicly available information on borrowersÂ’ default riskiness and the presence of guarantees on their bank loans; the second compares the interest rates charged on secured and unsecured loans made by different banks to the same borrower, thus perfectly controlling for idiosyncratic riskiness and singling out the direct effect of the presence of guarantees on credit risk. The empirical results show that real guarantees (physical assets or equities that the lender can sell if the borrower defaults), which are often internal, are mainly used to provide a priority to some creditors. Personal guarantees (contractual obligations of third parties to make payments in case of default, e.g. suretyships), which can only be external, are used instead as incentive devices against moral hazard problems. Controlling for borrowersÂ’ characteristics, both real and personal guarantees reduce ex-ante credit risk.Bank loans, collateral, guarantee

The Role of Guarantees in Bank Lending.

Guarantees play an important role in debt contracts. They alter the risk for the lender, transform borrowers' incentives and, possibly, modify the equilibrium allocation of financial resources. This paper studies the role of guarantees on bank loans, using a sample of over 50,000 individual lines of credit granted by Italian banks. Two empirical models are used. The first directly verifies the relationship between ex-ante publicly available information on borrowers' default riskiness and the presence of guarantees on their bank loans; the second compares the interest rates charged on secured and unsecured loans made by different banks to the same borrower, thus perfectly controlling for idiosyncratic riskiness and singling out the direct effect of the presence of guarantees on credit risk. The empirical results show that real guarantees (physical assets or equities that the lender can sell if the borrower defaults), which are often internal, are mainly used to provide a priority to some creditors. Personal guarantees (contractual obligations of third parties to make payments in case of default, e.g. suretyships), which can only be external, are used instead as incentive devices against moral hazard problems. Controlling for borrowers' characteristics, both real and personal guarantees reduce ex-ante credit risk.Bank loans, collateral, guarantee

Research and Development, Regional Spillovers and the Location of Economic Activities

I present an endogenous growth model that studies the effects of local inter-industry and intra-industry knowledge spillovers in R&D on the allocation of economic activities between two regions. The equilibrium is the result of a tension between a centripetal force, the cost of transporting goods from one region to the other, and a centrifugal force, the cost increase associated with life in a more crowded area. The presence of local knowledge spillovers, which determines the concentration of the R&D activities within one region, also introduces a further centripetal force that makes impossible a symmetric allocation of the economic activities. The concentration of R&D fosters the equilibrium rate of growth of the economy with respect to the case of no-integration, by increasing the positive effect of local knowledge spillovers. Contrary to the findings of the majority of models in the new economic geography literature, within this framework a reduction in the transport costs may be associated with a more even spatial location of economic activities.endogenous growth, local spillovers, regional location.

Endogenous Growth in Open Economies - A Survey of Major Results.

Endogenous growth has set a new paradigm for macroeconomic analysis. This paper overviews the most relevant theoretical contributions of this literature for the analysis of open economies, highlighting their implications both for the effects of crosscountry integration on output convergence and for the overall growth performance of the integrated economy, as compared to that of an identical group of autarchic countries. The literature is divided into three major classes, studying, respectively, the effects of factor mobility, the role of international trade, and the consequences of technology diffusion. The main conclusion is that knowledge spillovers can go a long way in explaining the differences in growth performances across countries, but additional research is needed to completely understand the mechanisms driving their international diffusion.endogenous growth, open economies, international spillovers.

On the Control of Non Holonomic Systems by Active Constraints

The paper is concerned with mechanical systems which are controlled by implementing a number of time-dependent, frictionless holonomic constraints. The main novelty is due to the presence of additional non-holonomic constraints. We develop a general framework to analyze these problems, deriving the equations of motion and studying the continuity properties of the "control-to-trajectory" maps. Various geometric characterizations are provided, in order that the equations be affine w.r.t. the time derivative of the control. In this case the system is fit for jumps, and the evolution is well defined also in connection with discontinuous control functions. The classical Roller Racer provides an example where the non-affine dependence of the equations on the derivative of the control is due only to the non-holonomic constraint. This is a case where the presence of quadratic terms in the equations can be used for controllability purposes.Comment: 26 pages, 3 figures. The current version will appear on Discrete and Continuous Dynamical Systems, Series

Growth performance, carcase characteristics and meat quality of crossbred bulls and heifers from double-muscled Belgian Blue sires and Brown Swiss, Simmental and Rendena dams

Growth, conformation, carcase and meat quality traits of crossbred calves obtained in the Alps from selected Belgian Blue sires (BB) and Brown Swiss (BS), Simmental (Si) and Rendena (Re) dams were studied, emphasising differences on dairy and dual purpose maternal breed. Six pens with five heifers (3 BB BS, 1 BB Si, 1 BB Re) and six pens with four young bulls (2 BB BS, 1 BB Si, 1 BB Re) were used. In total 53 crossbred calves were tested: 30 from BS dams and 23 from dual purpose (12 from Si and 11 from Re dams). Growth performances were measured, carcases were scored for muscle conformation and fatness, the fifth rib was dissected, and the Longissimus thoracis (LT) was analysed. The maternal breed had significant effects when the calves from dairy cows (BB BS) were compared to those of the dual pur- pose breeds (BB Si and BB Re), as at slaughter the former were 1.2% taller, 6.0% less in vivo muscle score, 5.0% less carcase muscle score, with a 13% greater proportion of bone in the rib, and their LT had 12.5% less drip losses, but 3% greater cooking losses and 25% greater shear force. It was concluded that when using a BB as a sire, the dam breed has influ- ence on the growth performance traits of the derived crossbreds, but the major influence would regard the carcase and meat quality traits. In the Alps, these differences are reflected in different sold prices of the crossbred calves from dairy and dual purpose breeds at local auctions

Chain recurrence, chain transitivity, Lyapunov functions and rigidity of Lagrangian submanifolds of optical hypersurfaces

The aim of this paper is twofold. On the one hand, we discuss the notions of strong chain recurrence and strong chain transitivity for flows on metric spaces, together with their characterizations in terms of rigidity properties of Lipschitz Lyapunov functions. This part extends to flows some recent results for homeomorphisms of Fathi and Pageault. On the other hand, we use these characterisations to revisit the proof of a theorem of Paternain, Polterovich and Siburg concerning the inner rigidity of a Lagrangian submanifold $\Lambda$ contained in an optical hypersurface of a cotangent bundle, under the assumption that the dynamics on $\Lambda$ is strongly chain recurrent. We also prove an outer rigidity result for such a Lagrangian submanifold $\Lambda$, under the stronger assumption that the dynamics on $\Lambda$ is strongly chain transitive.Comment: 26 pages, 2 figure

The Determinants of Cross-Border Bank Shareholdings; an Analysis with Bank-Level Data from OECD Countries

TThis paper investigates which factors determine a bank's decision to expand its activities abroad and what determines its choice of the countries to invest in. The empirical analysis is conducted using firm-level data on foreign subsidiaries for a representative sample of nearly 2,500 OECD banks. The results show that the banks with cross-border shareholdings are larger and have headquarters in countries with a more developed and efficient banking market. They prefer to invest in countries where expected profits are larger, owing to higher expected economic growth and the prospect of reducing local banks' inefficiency. These factors are overall more important in banksÂ’ decisions than those related to the degree of openness of the origin country and its economic integration with the destination country.banks, foreign banks, foreign direct investment