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Bucharest, Romania

The Bucharest University of Economic Studies is a public university in Bucharest, Romania. Founded in 1913 as the Academy of High Commercial and Industrial Studies ), it has become one of the largest higher education institutes in both Romania and South-Eastern Europe. Wikipedia.

Cotfas L.-A.,Academy of Economic Studies Bucharest
AIP Conference Proceedings | Year: 2012

The trade of a fixed stock can be regarded as the basic process that measures its momentary price. The stock price is exactly known only at the time of sale when the stock is between traders, that is, only in the case when the owner is unknown. We show that the stock price can be better described by a function indicating at any moment of time the probabilities for the possible values of price if a transaction takes place. This more general description contains partial information on the stock price, but it also contains partial information on the stock owner. By following the analogy with quantum mechanics, we assume that the time evolution of the function describing the stock price can be described by a Schrödinger type equation. © 2012 American Institute of Physics. Source

Cotfas L.-A.,Academy of Economic Studies Bucharest
Physica A: Statistical Mechanics and its Applications | Year: 2013

We present a finite-dimensional version of the quantum model for the stock market proposed in C. Zhang and L. Huang [A quantum model for the stock market, Physica A 389 (2010) 5769]. Our approach is an attempt to make this model consistent with the discrete nature of the stock price and is based on the mathematical formalism used in the case of the quantum systems with finite-dimensional Hilbert space. The rate of return is a discrete variable corresponding to the coordinate in the case of quantum systems, and the operator of the conjugate variable describing the trend of the stock return is defined in terms of the finite Fourier transform. The stock return in equilibrium is described by a finite Gaussian function, and the time evolution of the stock price, directly related to the rate of return, is obtained by numerically solving a Schrödinger type equation. © 2012 Elsevier B.V. All rights reserved. Source

Dragomir V.D.,Academy of Economic Studies Bucharest
Journal of Cleaner Production | Year: 2012

The European body of research on corporate environmental performance has not yet reached maturity. That is mainly due to the limited access researchers have to raw environmental performance data, in conjunction with an often sterile approach to developing proxies and indicators for this type of corporate performance. Moreover, annual sustainability reports are often neglected in spite of their capacity to produce a compelling longitudinal research perspective. The present article offers a critical reading of the last decade's sustainability reports from the top five largest European oil and gas companies. On account of their significant contribution to global warming, the sample companies (i.e. BP, Total, Shell, BG Group and Eni) have been scrutinized for their ability to provide high-quality environmental disclosures at group-level. Given the sophistication of emissions data collection and estimation tools such as the Greenhouse Gas (GHG) Protocol, it comes as a surprise that these five industry leaders have issued reports containing unexplained figures and methodological inconsistencies. Finally, the reader is persuaded that empirical research in the field of corporate environmental performance should mostly be about creating a context for discussing a firm's commitment to sustainability, rather than modelling irrelevant cross-sectional data to find similarities between incomparable cases. © 2012 Elsevier Ltd. All rights reserved. Source

Toma A.,Academy of Economic Studies Bucharest
Economic Computation and Economic Cybernetics Studies and Research | Year: 2012

We consider a new robust estimation method based on pseudodistances minimization. Unlike other existing methods of this type, such as minimum Hellinger distance estimation, the proposed approach avoid the use of nonparametric density estimation and associated complications such as bandwidth selection. The proposed class of estimators is indexed by a single parameter α which controls the trade-off between robustness and efficiency. The method is applied to expected return and volatility estimation of financial asset returns under normality. Empirical results on simulated or financial data prove the performance of this method. Source

Georgescu I.,Academy of Economic Studies Bucharest
Soft Computing | Year: 2011

In this paper a possibilistic model of risk aversion based on the lower and upper possibilistic expected values of a fuzzy number is studied. Three notions of possibilistic risk premium are defined for which calculation formulae in terms of Arrow-Pratt index and a possibilistic variance are established. A possibilistic version of Pratt theorem is proved. © 2010 Springer-Verlag. Source

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