An information-based adaptive strategy for resource exploitation in competitive scenarios

Given an exploitation problem, in which a number of agents compete for a limited renewable resource, the optimal harvesting strategy depends on the ratio between resource availability and exploitation effort. For scarce resource a purely competitive, greedy strategy outperforms a more collaborative approach based on the Collective Intelligence, while for more abundant resource the opposite holds. The rationale for this behaviour lies in the amount of information each strategy is able to provide and a combined strategy is possible according to which agents choose dynamically the most informative strategy according to a minimum entropy criterion. This approach, which provides best performance for both under and over-exploited scenarios, can be used to monitor the resource status for management purposes and is effective in both centralised and decentralised decision making.     

Portfolio flows and the US dollar–yen exchange rate

This paper investigates the effects of portfolio flows on the US dollar–Japanese yen exchange rate changes over the period 1988:01–2011:04. Using a time-varying transition probability Markov-switching framework, the results suggest that the impact of portfolio flows on the dollar–yen exchange rate changes is state-dependent. In particular, the results show that portfolio inflows from Japan toward the US, more than monetary variables, strengthen the probability of remaining in the dollar–yen appreciation (low volatility) state. Therefore, credit controls on the flows can be used as a policy tool to pursue economic and financial stability.     

Social cooperatives,social welfare associations and social networks

We use an original data-set to study how participation in two types of non-profit organizations – i.e. social welfare associations and social cooperatives – affects individual social capital, understood as a network of cooperative relationships. Participation in both the types of organization allows members to start new social relations. However, social welfare associations seem to play a significantly greater role in the development of volunteers’ social capital, favouring the creation of weak ties that are used to exchange information and advice, and offering the opportunity to establish stronger ties entailing concrete mutual support. Within social cooperatives, workers appear to develop their individual social capital to a greater extent than volunteers. Our results suggest that the composition of the workforce, the depth of members’ involvement in the organization’s activities and the human resources strategies adopted by the management influence the creation of cooperative relations through on-the-job interactions.     

I do not own a car any more: An analysis of possessions’ disposal and changes in consumers’ identities

This research aims to understand the process of cars' disposal, its context, its influences and its impacts on the meanings for consumers and their identities, as well as the new behaviours of these consumers when living without their car(s). We conducted, analysed and interpreted 20 in‐depth interviews with consumers that had previously owned at least one car and had no financial reasons for disposing of their car(s), but had decided to do it, and started to live without them, adopting alternative methods of transportation. Our findings show that these consumers faced a complicated process regarding the disposal of their car(s) but, due to the changes in their circumstances, they re‐signified relevant concepts that were connected to the ownership of a car: Their perception of freedom, comfort, safety and status changed during and after the disposal of their car(s). We also noticed that there were implications in terms of changes in their attitudes and behaviour as both citizens and consumers. As a contribution to the literature, our findings indicate that the re‐signifying of concepts related to possession of the object as well as changes in attitudes and behaviours that consumers undergo in the postdisposal stage, must be included in the model proposed for evaluating consumer behaviour in product disposal.     

Heterogeneous duopoly with isoelastic demand function

In this paper we analyze a duopolistic market with heterogeneous firms when the demand function is isoelastic (Puu, T., 1991. Chaos in duopoly pricing. Chaos, Solitons and Fractals 1, 573–581.). We consider the same heterogeneous firms of Zhang et al. (Zhang, J., Da, Q., Wang, Y., 2007. Analysis of nonlinear duopoly game with heterogeneous players. Economic Modelling 24, 138–148.) introducing a nonlinearity in the demand function instead of the cost function. Stability conditions of the Nash equilibrium and complex dynamics are studied. In particular we show two different routes to complicated dynamics: a cascade of flip bifurcations leading to periodic cycles (and chaos) and the Neimark-Sacker bifurcation which originates an attractive invariant closed curve. Comparisons with respect to the Puu model and the model of Zhang et al. are performed.     

Global slack and domestic inflation rates: A structural investigation for G-7 countries

Recent papers have argued that one implication of globalization is that domestic inflation rates may have now become more a function of “global”, rather than domestic, economic conditions, as postulated by closed-economy Phillips curves.This paper aims to assess the empirical importance of global output in determining domestic inflation rates by estimating a structural model for a sample of G-7 economies. The model can capture the potential effects of global output fluctuations on both the aggregate supply and the aggregate demand relations in the economy and it is estimated using full-information Bayesian methods.The empirical results reveal a significant effect of global output on aggregate demand in most countries. Through this channel, global economic conditions can indirectly affect inflation. The results, instead, do not seem to provide evidence in favor of altering domestic Phillips curves to include global slack as an additional driving variable for inflation.     

Short- and long-run heterogeneous investment dynamics

In this paper, we model the dynamics of business investment taking into account asset-specific characteristics potentially affecting the reactivity of aggregate and disaggregate capital accumulation over the business cycle. We estimate Information and Communication Technologies (ICTs) and traditional investment (non-ICT) determinants within a Vector Error Correction Model testing the assumptions of the flexible accelerator and neoclassical model as well as the role of financial constraints and uncertainty. We evaluate our model on Italian data over the period 1980–2012, and we check our results also with Spanish and UK data. Our findings support the assumption that capital is heterogeneous since short- and long-run determinants are significantly different across the assets. Traditional assets experience stock adjustment costs while ICT investment incurs flow adjustment cost. In the short run, liquidity is a key determinant of investment independently of the asset type. In the long run, uncertainty significantly affects ICT. Finally, the results of the counterfactual exercises support the idea that ICT is a key policy variable to foster economic growth.     

A model of the Italian cut-off system for taxing small businesses

The Studi di Settore are used by the Italian tax administration to calculate reference revenue levels for small businesses and provide a kind of cut-off level for tax audits. Recently new rules have been introduced in order to render the Studi di Settore more efficient in producing realistic estimates, with the aim of reducing the “legalized evasion” that might arise in case of a systematic downward bias. Voices of the involved categories, however, convinced the Government to partially step back. Building upon the standard firm’s tax evasion model of Cowell [Cowell, F.A., 2004. Carrots and sticks in enforcement. In: Aaron, H.J., Slemrod, J. (Eds.), The Crisis in Tax Administration. The Brookings Institution, Washington DC, pp. 230–275] and the approach of Santoro [Santoro, A.C., 2006. Evasione delle società di capitali: evidenze empiriche e proposte di policy. In: Brosio, G., Muraro, M. (Eds.), Il Finanziamento del Settore Pubblico. SIEP, Angeli, Milano, pp. 163–186] we show that, under given conditions, a stringency increase might backfire implying a larger overall tax evasion and a smaller tax revenue.     

The time-varying independence of Italian peak judicial institutions

The paper investigates the stability of the degree of independence of the judiciary vis à vis both the classical political branches and other independent institutions, such as regulatory agencies, using evidence about the Italian Constitutional Court and the Council of State. Both peak judicial courts feature time varying factors of independence that affect their jurisprudence, especially in the case of the legitimacy review by the Constitutional Court. The less conclusive evidence found in the Council of State related to decisions of independent regulatory authorities might be due to the more complex set of interactions in which the Council operates.     

Accurate Short-Term Yield Curve Forecasting using Functional Gradient Descent

We propose a multivariate nonparametric technique for generatingreliable short-term historical yield curve scenarios and confidenceintervals. The approach is based on a Functional Gradient Descent(FGD) estimation of the conditional mean vector and covariancematrix of a multivariate interest rate series. It is computationallyfeasible in large dimensions and it can account for nonlinearitiesin the dependence of interest rates at all available maturities.Based on FGD we apply filtered historical simulation to computereliable out-of-sample yield curve scenarios and confidenceintervals. We back-test our methodology on daily USD bond datafor forecasting horizons from 1 to 10 days. Based on severalstatistical performance measures we find significant evidenceof a higher predictive power of our method when compared toscenarios generating techniques based on (i) factor analysis,(ii) a multivariate CCC-GARCH model, or (iii) an exponentialsmoothing covariances estimator as in the RiskMetrics^TM approach.