Growth and social capital: an evolutionary model

In this paper, we analyze the role of cooperation between firms through a model of growth and social capital. In a growth model à la Solow we incorporate the set of resources that a relational network has at its disposals, as a distinct production factor, and thus examine its dissemination through evolutionary type processes in firm interactions. Dynamic analysis of the model demonstrates that cooperation is able to increase the productivity of factors, fostering a higher rate of growth in the long term. The most significant result is that scarcity of social capital can produce a general collapse of the economic system in areas in which long term growth is usually sustained by the learning by doing and spillover of knowledge phenomena. This conclusion leads to reconsider the role of local development economic policies that should concentrate on activities that promote repeated interaction between firms proven to be cooperative or that encourage the formation of technological consortia.     

Pervasive inattentiveness

In this paper we analyze how inattentiveness in capital investment decisions shapes business cycle dynamics in a dynamic stochastic general equilibrium (DSGE) model with inattentiveness. We find that the model with pervasive inattentiveness matches several business cycle moments much better than an otherwise identical model without informational frictions in investment. These findings reinforce the need for pervasive stickiness to mimic the inertia found in macroeconomic data.     

The Heisenberg picture in the analysis of stock markets and in other sociological contexts

We review some recent results concerning some toy models of stock markets. Our models are suggested by the discrete nature of the number of shares and of the cash which are exchanged in a real market, and by the existence of conserved quantities, like the total number of shares or some linear combination of the cash and the shares. This suggests to use the same tools used in quantum mechanics and, in particular, the Heisenberg picture to describe the time behavior of the portfolio of each trader. We finally propose the use of this same framework in other sociological contexts.     

Do Institutions and Culture Matter for Business Cycles?

We examine the relationship between cyclical fluctuations and macroeconomic, institutional, and cultural indicators for 46 countries from Europe and the Mediterranean basin. In the Mediterranean cycles are different: the duration of expansions is shorter; the amplitude of recessions is larger; and cyclical synchronization is smaller than elsewhere. Differences in cultural indicators have strong and significant associations with differences in the persistence and volatility of cyclical fluctuations and their synchronization.     

Production smoothing, firms' heterogeneity, and financial constraints: evidence from a panel of UK firms

In this paper we provide an empirical analysis of heterogeneityin firms' inventory behavior, using a panel of UK manufacturingfirms. We first investigate how the relative variance of productionand sales differs across firms. We then use variants of thelinear quadratic inventory model in order to analyze potentialheterogeneity in firms' incentives to smooth production. Theresults suggest that incentives to smooth production are notprevalent This conclusion also holds when firms are partitionedaccording to whether they are more or leu likely to face finanrialconstraints.     

Second Best Environmental Policies under Uncertainty

We construct a strategic environmental policy model of an international duopoly. Governments use environmental policies, such as an emissions standard or a tax, to control pollution and for rent shifting purposes. Contrary to firms, however, governments are unable to perfectly foresee the actual level of demand and the cost of abatement. Our results suggest that not only the presence but also the absolute level of uncertainty matters for the optimal choice of the environmental policy instrument. Moreover, the optimality conditions under strategic behavior may lead to welfare losses relative to the cooperative outcomes because of under‐regulation and lack of policy coordination between the two countries.     

A characterization for solutions of stochastic discrete time optimization models

A notion of finitely optimal plan for intertemporal optimization problems as a necessary condition for optimality is introduced. Under interiority of a feasible plan and differentiability of the return function, such a plan satisfies the stochastic analogue of deterministicEuler-Lagrange conditions, which become also sufficient conditions under concavity of the return function. Then, under more general assumptions, a sufficient criterion of optimality based on competitive plans supported by price systems and transversality conditions is discussed. Differently from the current literature, no restrictive hypotheses on the probability measure of the random shocks are assumed.

---

Sommario Nella prima parte del lavoro si studiano le soluzioni dettefinitamente ottime che costituiscono una condizione necessaria per l'ottimalità di un piano ammissibile . Sotto ipotesi di interiorità del piano ammissibile e di differenziabilità della funzione obiettivo uniperiodaleF, vengono formulate le condizioni necessarie diEuler-Lagrange in ambito stocastico; aggiungendo l'ulteriore ipotesi di concavità perF, tali condizioni diventano anche sufficienti per l'ottimalità finita.La teoria viene poi estesa al caso sopradifferenziabile ottenendo una generalizzazione delle condizioni di Euler-Lagrange stocastiche che consente di individuare i piani finitamente ottimi mediante la nozione dicompetitività, ovvero supportabilità di un sistema di prezzi aleatori. Con una condizione di trasversalità all'infinito, la competitività diventa condizione sufficiente anche per l'ottimalità propria (cioè non solo finita).La peculiarità della presente trattazione è che tali condizioni sono formulate sotto ipotesi molto generali per quanto riguarda il processo degli shocks esogeni.

     

Business cycle synchronisation in East Asia

Against the background of the rapid inter- and intra-regional integration of East Asia, we examine the extent and nature of synchronisation of business cycles in the region. We estimate a dynamic common factor model for output growth of 10 East Asian countries. A significant common factor is shared by all Asian countries considered, except China and Japan. The degree of synchronisation has fluctuated over time, with an upward trend particularly evident for the newly industrialised economies. Synchronisation appears to mainly reflect strong export synchronisation, rather than common consumption or investment dynamics. A number of external factors, such as the oil price and the JPY–USD exchange rate, appear to play a role in synchronising activity.     

Some reflections on past and future of nonlinear dynamics in economics and finance

This paper offers an overview of the literature on the economic and financial applications of theory of nonlinear dynamics, especially bifurcation theory. After a short introductory discussion of the first nonlinear dynamic models in social sciences and the economic relevance of the zoo of bifurcations and complicated dynamics that such models can generate, we present an overview of the literature on nonlinear dynamic models in the areas of underdevelopment, environmental poverty traps, the management of common goods, industrial organization and financial markets. The review of the literature is enriched by reflections and ideas for future research.