Some Further Evidence about Magnification and Shape in Neural Gas

Neural gas (NG) is a robust vector quantization algorithm with a well-known mathematical model. According to this, the neural gas samples the underlying data distribution following a power law with a magnification exponent that depends on data dimensionality only. The effects of shape in the input data distribution, however, are not entirely covered by the NG model above, due to the technical difficulties involved. The experimental work described here shows that shape is indeed relevant in determining the overall NG behavior; in particular, some experiments reveal richer and complex behaviors induced by shape that cannot be explained by the power law alone. Although a more comprehensive analytical model remains to be defined, the evidence collected in these experiments suggests that the NG algorithm has an interesting potential for detecting complex shapes in noisy datasets

Lender of Last Resort and Bank Closure Policy

During the last decades a consensus has emerged that it is impossible to disentangle liquidity shocks from solvency shocks. As a consequence the classical lender of last resort rules, as defined by Thornton and Bagehot, based on lending to solvent illiquid institutions appear ill-suited to this environment. We summarize here the main contributions that have developed considering this new paradigm and discuss how institutional features relating to bank closure policy influences lender of last resort and other safety net issues. We devote particular emphasis to the analysis of systemic risk and contagion in banking and the role of the lender of last resort to prevent it.lender of last resort, systemic risk, contagion, bank closure, liquidity, discount window

Diversification and Ownership Concentration

In a mean-variance economy where controlling shareholders can divert profits, equity ownership is more concentrated the higher the stock returns correlation. A higher returns correlation reduces the benefits of diversification, giving rise to both a higher investment by the controlling shareholder in the asset that he controls and a lower investment by the non-controlling shareholders. The empirical analysis supports the predictions of the model. In particular, controlling for measures of the quality of investor protection, and other structural variables, we find that equity ownership is significantly more concentrated in countries where the stock returns correlation is higher. Moreover the intensity of the relationship between the stock returns correlation and ownership concentration is amplified by poor investor protection.Ownership concentration,Diversificationopportunities,Investor protection.

Connections and Performance in Bankers' Turnover: Better Wed over the Mixen than over the Moor

In this paper we study top executive turnover in Italian Banks over the period 1993-2001. We relate the probability of survival of top executives (Presidents, CEOs and General Managers) to bank performance and the manager’s local connections, controlling for (observable and unobservable) bank and manager characteristics by exploiting longitudinal information on bank-manager appointments. We measure the extent? of managers’ local connections by the distance between the province of the bank’s headquarters and the manager’s province of birth. We show that top managers tend to be local in the sense that the distribution of this distance is heavily skewed towards zero. On the basis of this evidence, we address two questions. First, we investigate whether connections affect the duration of the appointment at the bank. Second, we ask whether connections entrench managers at the expense of the bank’s performance. We find that connections generally increase the probabilities of managerssurviving at their banks, and that the positive effect of performance on tenure (as amply documented by the executive turnover literature) disappears once connections are taken into account. On the other hand, we provide evidence against the hypothesis that managerial connections contain information valuable for enhancing a bank’s performance. In particular, we find that highly connected boards cause the shorter survival of banks, and that those who benefit from connections are top managers themselves (mostly Presidents and General Managers). This suggests that connections may be collusion devices with which to maintain and share rents.connections, executive turnover, commercial and cooperative banks

Forecasting Industrial Production in the Euro Area

The creation of the Euro area has increased the importance of obtaining timely information about short-term changes in the area's real activity. In this paper we propose a number of alternative short-term forecasting models, ranging from simple ARIMA models to more complex cointegrated VAR and conditional models, to forecast the index of industrial production in the euro area. A conditional error-correction model in which the aggregate index of industrial production for the area is explained by the US industrial production index and the business confidence index from the European Commission harmonised survey on manufacturing firms achieves the best score in terms of forecasting capacity.

What is this thing called confidence? A comparative analysis of consumer confidence indices in eight major countries

The paper examines the evolution of consumer confidence indices in Australia, Canada, France, Germany, Italy, Japan, the United Kingdom and the United States of America since the 1970s, by modelling them in a multivariate framework of common macroeconomic variables for each country. Results suggest that: (a) the main economic determinants of consumer confidence cannot be summarized only on the basis of some macroeconomic variables; (b) consumer confidence indices have some ability to forecast economic activity, provided that both their coincident nature is taken into account and that a number of data-coherent parameter restrictions are imposed. A number of analyses (both insample and out-of-sample) are devoted to assessing the robustness of previous findings.consumer confidence determinants, GDP indicator, in-sample and out-of-sample forecasting ability

Statistical signatures of multimode single-photon added and subtracted states of light

The addition or subtraction of a photon from a Gaussian state of light is a versatile and experimentally feasible procedure to create non-Gaussian states. In multimode setups, these states manifest a wide range of phenomena when the photon is added or subtracted in a mode-tunable way. In this contribution, we derive the truncated correlations, which are multimode generalisations of cumulants, between quadratures in different modes as statistical signatures of these states. These correlations are then used to obtain the full multimode Wigner function, the properties of which are subsequently studied. In particular we investigate the effect of impurity in the subtraction or addition process, and evaluate its impact on the negativity of the Wigner function. Finally, we elaborate on the generation of inherent entanglement through subtraction or addition of a photon from a pure squeezed vacuum.Comment: 27 pages (incl. appendix), 6 figure