Recognizing and forecasting the sign of financial local trends using hidden Markov models

The problem of forecasting financial time series has received great attention in the past, from both Econometrics and Pattern Recognition researchers. In this context, most of the efforts were spent to represent and model the volatility of the financial indicators in long time series. In this paper a different problem is faced, the prediction of increases and decreases in short (local) financial trends. This problem, poorly considered by the researchers, needs specific models, able to capture the movement in the short time and the asymmetries between increase and decrease periods. The methodology presented in this paper explicitly considers both aspects, encoding the financial returns in binary values (representing the signs of the returns), which are subsequently modelled using two separate Hidden Markov models, one for increases and one for decreases, respectively. The approach has been tested with different experiments with the Dow Jones index and other shares of the same market of different risk, with encouraging results

On the use of SIFT features for face authentication

Several pattern recognition and classification techniques have been applied to the biometrics domain. Among them, an interesting technique is the Scale Invariant Feature Transform (SIFT), originally devised for object recognition. Even if SIFT features have emerged as a very powerful image descriptors, their employment in face analysis context has never been systematically investigated. This paper investigates the application of the SIFT approach in the context of face authentication. In order to determine the real potential and applicability of the method, different matching schemes are proposed and tested using the BANCA database and protocol, showing promising results

Understanding critical factors in gender recognition

Gender classification is a task of paramount importance in face recognition research, and it is potentially useful in a large set of applications. In this paper we investigate the gender classification problem by an extended empirical analysis on the Face Recognition Grand Challenge version 2.0 dataset (FRGC2.0). We propose challenging experimental protocols over the dimensions of FRGC2.0 – i.e., subject, face expression, race, controlled or uncontrolled environment. We evaluate our protocols with respect to several classification algorithms, and processing different types of features, like Gabor and LBP. Our results show that gender classification is independent from factors like the race of the subject, face expressions, and variations of controlled illumination conditions. We also report that Gabor features seem to be more robust than LBPs in the case of uncontrolled environment

Robust visual servoing in 3d reaching tasks

This paper describes a novel approach to the problem of reaching an object in space under visual guidance. The approach is characterized by a great robustness to calibration errors, such that virtually no calibration is required. Servoing is based on binocular vision: a continuous measure of the end-effector motion field, derived from real-time computation of the binocular optical flow over the stereo images, is compared with the actual position of the target and the relative error in the end-effector trajectory is continuously corrected. The paper outlines the general framework of the approach, shows how visual measures are obtained and discusses the synthesis of the controller along with its stability analysis. Real-time experiments are presented to show the applicability of the approach in real 3-D applications

Il ruolo del confine nelle trasformazioni della nozione giuridica di cittadinanza

Starting from the statement that there is a close link between the idea of the «border» (and more generally of any kind of «boundary») and a notion of citizenship whatsoever, the author analyses, among many possible meanings, two «ideal types» which have differently had a part in the process of modern State building, contributing to clarify that the citizenship has to do with the idea of separation, exclusion and difference, much more than with the idea of integration and inclusion. The citizenship can be conceived in a «vertical» meaning, that is a relationship between the individual and the sovereign, or in a «horizontal» meaning, that is a collective identity, binding all individuals on the basis of a common political membership. After following the «great neutralisation» of the Nineteenth Century, when citizenship changes into a new «national» dimension, becoming properly a «nationality», the author focus on two clear examples of «political use» (or, as we could also say, «political manipulation») of the notion of citizenship: in USA at the time of the adoption of XIV Amendment in 1865 and in France, between the end of Napoleonic Age and the middle of Twentieth Century. At that time the border plays a new role, including and excluding from time to time new categories of people, depending on political and historical needs of the moment. Some considerations are finally developed about the political relationship between citizenship and the notion of border in the Twentieth Century’s Constitutional State, when the idea of a «national» citizenship, sometimes as vertical relationship between the individual and the State, sometimes as consciousness of a collective membership, is still at the heart of our legislation, with the political aim to keep the distances, and strenuously defend the borders, between the «lucky» citizens of the rich developed world from one side, and the new «wretched of the Earth» from the other side