Self-organizing social hierarchies on scale-free networks

In this work we extend the model of Bonabeau et al. in the case of scale-free networks. A sharp transition is observed from an egalitarian to an hierarchical society, with a very low population density threshold. The exact threshold value also depends on the network size. We find that in an hierarchical society the number of individuals with strong winning attitude is much lower than the number of the community members that have a low winning probability

The real effects of financial stress in the Euro zone

Using two identification strategies based on a Bayesian Structural VAR and a Sign-Restriction VAR, we examine the real effects of financial stress in the Eurozone. In particular, we assess the macroeconomic impact of: (i) a monetary policy shock; and (ii ) a financial stress shock. We find that a monetary policy contraction strongly deteriorates financial stress conditions. In addition, unexpected variation in the Financial Stress Index (FSI) plays an important role in explaining output fluctuations, and also demands an aggressive response by the monetary authority to stabilise output indicating a preference shift from targeting inflation as it is currently happening in major economies. Therefore, our paper reveals the importance of adopting a vigilant posture towards financial stress conditions, as well as the urgency of macro-prudential risk management.monetary policy, financial stress, Bayesian Structural VAR, Sign-Restrictions, Euro-zone.

Monetary Policy Rules in the BRICS: How Important is Nonlinearity?

Given limited research on monetary policy rules in emerging markets, this paper estimates monetary policy rules for five key emerging market economies: Brazil, Russia, India, China and South Africa (BRICS) analysing whether the monetary authority reacts to changes in financial markets, in monetary conditions, in the foreign exchange sector and in the commodity price. To get a deeper understanding of the central bank’s behaviour, we assess the importance of nonlinearity using a smooth transition (STAR) model. Using quarterly data, we find strong evidence that the monetary policy followed by the Central Banks in the BRICS varies from one country to another and that it exhibits nonlinearity. In particular, considerations about economic growth (in the cases of Brazil and Russia), inflation (for India and China) and stability of financial markets (in South Africa) seem to be the major drivers of such nonlinear monetary policy behaviour. Moreover, the findings suggest that the monetary authorities pursue, with the exception of India, a target range for the threshold variable rather than a specific point target. In fact, the exponential smooth transition regression (ESTR) model seems to be the best description of the monetary policy rule in these countries.monetary policy, emerging markets, smooth transition.

Estimating and controlling the traffic Impact of a collaborative P2P system

Nowadays, P2P applications are commonly used in the Internet being an important paradigm for the development of distinct services. However, the dissemination of P2P applications also entails some important challenges that should be carefully addressed. In particular, some of the important coexistence problems existing between P2P applications and Internet Service Providers (ISPs) are mainly motivated by the inherent P2P dynamics which cause traffic to scatter across the network links in an unforeseeable way. In this context, this work proposes a collaborative framework of a Bit- Torrent like system. Using the proposed framework and based on the exchange of valuable information between the application and network levels, some novel techniques are proposed allowing to estimate and control the traffic impact that the P2P system will have on the links of the underlying network infrastructure. Both the framework and the presented techniques were tested resorting to simulation. The results clearly corroborate the viability and effectiveness of the formulated methods

AN ECONOMIC ANALYSIS OF THE RELATIONSHIP OF POVERTY AND INCOME INEQUALITY IN RURAL WEST VIRGINIA

Ordinary and two-stage least square regressions were used to examine the major determinants of poverty and income inequality with cross-sectional data of 38 rural counties of West Virginia. The empirical findings confirm the possibility of simultaneity between poverty and income inequality and poverty level is the main determinant of increased levels of income inequality. The proportions of population in welfare, population of age 65 or older, female-headed households, people unemployed, and the level of inequality contributed to increased poverty levels. The proportion of employment shares in finance, insurance and real estate, and per capita income contributed to reduced poverty levels. But, per capita income, the proportion of human capital stock, and the proportion of employment shares in manufacturing contributed to reduced income inequality.Food Security and Poverty,