Search results for " ANN"

Information and Investor Behavior Surrounding Earnings Announcements

2014

Preliminary version The goal of this paper is to analyze the impact of annual earnings announcements on the market through the order flow data in addition to the usual transaction data. In this respect, examining order flow data can potentially reveal valuable information which is not available from transaction data. In fact, the data allow us to test hypotheses about asymmetric information and investor behavior and to test if the behavior varies with investor sophistication. In addition, the paper tries to identify the determinants of the impact on a firm's value using assumptions about investor behavior.

A model for designing callable bonds and its solution using tabu search

1997

Abstract We formulate the problem of designing callable bonds as a non-linear, global, optimization problem. The data of the model are obtained from simulations of holding-period returns of a given bond design, which are used to compute a certainty equivalent return, viz., some target assets. The design specifications of the callable bond are then adjusted so that the certainty equivalent return is maximized. The resulting problem is multi-modal, and a tabu search procedure, implemented on a distributed network of workstations, is used to optimize the bond design. The model is compared with the classical portfolio immunization model, and the tabu search solution technique is compared with s…

A problem-adjusted genetic algorithm for flexibility design

2013

Many present markets for goods and services have highly volatile demand due to short life cycles and strong competition in saturated environments. Determination of capacity levels is difficult because capacities often need to be set long before demand realizes. In order to avoid capacity-demand mismatches, operations managers employ mix-flexible resources which allow them to shift excess demands to unused capacities. The Flexibility Design Problem (FDP) models the decision on the optimal configuration of a flexible (manufacturing) network. FDP is a difficult stochastic optimization problem, for which traditional exact approaches are not able to solve but the smallest instances in reasonable…

The informational role of thin options markets: Empirical evidence from the Spanish case

2016

This study investigates the informational role of thin options markets, specifically the Spanish options market. Firstly, we examine the effect of options markets by analysing stock market reaction to earnings news, conditional on the availability of options markets. Secondly, we examine options trading activity before the release of earnings news (including the announcement period). The results show that the impact on prices before the earnings release is significantly bigger when options trading is available. Moreover, the dissemination of earnings news is associated with significant unusual activity in the options market due to informed trading, especially when the earnings surprise is h…

TERRA IN EQUILIBRIO, la natura per il sociale

2004

Le cours magistral en première année universitaire : de la construction des pratiques d’enseignement à l’analyse de leurs effets sur la scolarité des…

2022

High‐temperature behavior of impurities and dimensionality of the charge transport in unintentionally and tin‐doped indium selenide

1993

A systematic study of the electron transport and shallow impurity distribution in indium selenide above room temperature or after an annealing process is reported by means of far‐infrared‐absorption and Hall‐effect measurements. Evidences are found for the existence of a large concentration of deep levels (1012–1013 cm−2), related to impurities adsorbed to stacking faults in this material. Above room temperature impurities can migrate from those defect zones and then become shallow in the bulk. The subsequent large increase of 3D electrons can change the dimensionality of the electron transport, which in most cases was 2D. The temperature dependence of the resistivity parallel to the c axis…

In silico characterization of the neural alpha tubulin gene promoter of the sea urchin embryo Paracentrotus lividus by phylogenetic footprinting

2011

During Paracentrotus lividus sea urchin embryo development one alpha and one beta tubulin genes are expressed specifically in the neural cells and they are early end output of the gene regulatory network that specifies the neural commitment. In this paper we have used a comparative genomics approach to identify con- served regulatory elements in the P. lividus neural alpha tubulin gene. To this purpose, we have first isolated a genomic clone containing the entire gene plus 4.5 Kb of 5 0 upstream sequences. Then, we have shown by gene transfer experiments that its non-coding region drives the spatio- temporal gene expression corresponding substantially to that of the endogenous gene. In addi…

Defining the genomic signature of totipotency and pluripotency during early human development.

2013

The genetic mechanisms governing human pre-implantation embryo development and the in vitro counterparts, human embryonic stem cells (hESCs), still remain incomplete. Previous global genome studies demonstrated that totipotent blastomeres from day-3 human embryos and pluripotent inner cell masses (ICMs) from blastocysts, display unique and differing transcriptomes. Nevertheless, comparative gene expression analysis has revealed that no significant differences exist between hESCs derived from blastomeres versus those obtained from ICMs, suggesting that pluripotent hESCs involve a new developmental progression. To understand early human stages evolution, we developed an undifferentiation netw…

Chameleonic appearance of caseous calcification of the mitral valve – still a problem for its appropriate management

2021

According to the research literature, the caseous calcification of the mitral annulus (CCMA) is a rare variant of the mitral annulus calcification (MAC) entity, described mostly in elderly women. The aim of this study was to present the case of a 53-year-old female patient with caseous calcification of the mitral valve annulus and posterior cusp, which was diagnosed as papillary fibroelastoma. An echo-dense and quasi-homogeneous tumoral mass, measuring 1.6/1.4 cm, at the level of the posterior mitral ring was detected by echocardiographic examination, as well as by cardiac magnetic resonance imaging (MRI). Histopathological analysis revealed fibrous connective tissue with myxoid areas, hyal…