A probabilistic analysis of a leader election algorithm

A {\em leader election} algorithm is an elimination process that divides recursively into tow subgroups an initial group of n items, eliminates one subgroup and continues the procedure until a subgroup is of size 1. In this paper the biased case is analyzed. We are interested in the {\em cost} of the algorithm, i.e. the number of operations needed until the algorithm stops. Using a probabilistic approach, the asymptotic behavior of the algorithm is shown to be related to the behavior of a hitting time of two random sequences on [0,1]

Crisis Propagation and Governance

Following the appearance of the recent scandals, the question of the efficiency of the corporate governance mechanisms to appease the financial crisis can be raised. The purpose of this paper is to study the impact of the board of directors effectiveness on the firm's ability to resist the Asian stock market crisis. The firm ability to resist the Asian stock market crisis is assessed by minimization of financial return's conditional volatility estimated by ARCH and GARCH models. Using a data from 94 listed and industrial firms in four East Asian countries: Malaysia, Thailand, Indonesia, and the Philippines between 1996 and 1998, we find that the board size and the presence of the outside directors are negatively linked to the financial return's conditional volatility. This result seems to be compatible with the argument which supposes that the efficient boards can increase the ability to control the managers and the capability of firms to resist the crisis. The leadership structure would be without effect on the resistance to the crisis and the CEO turnover would have a positive effect on the financial return's conditional volatility.corporate governance, board of directors, propagation of crisis, financial return's conditional volatility

Energy loss and inelastic diffraction of fast atoms at grazing incidence

The diffraction of fast atoms at grazing incidence on crystal surfaces (GIFAD) was first interpreted only in terms of elastic diffraction from a perfectly periodic rigid surface with atoms fixed at equilibrium position. Recently, a new approach have been proposed, referred here as the quantum binary collision model (QBCM). The QBCM takes into account both the elastic and inelastic momentum transfer via the Lamb-Dicke probability. It suggests that the shape of the inelastic diffraction profiles are log-normal distributions with a variance proportional to the nuclear energy loss deposited on the surface. For keV Neon atoms impinging the LiF surface, the predictions of the QBCM in its analytic version are compared with numerical trajectory simulations. Some of the assumptions such as the planar continuous form, the possibility to neglect the role of lithium atoms and the influence of temperature are investigated. A specific energy loss dependence $\Delta E\propto\theta^7$ is identified in the quasi-elastic regime merging progressively to the classical onset $\Delta E\propto\theta^3$. The ratio of these two predictions highlight the role of quantum effects in the energy loss.Comment: 9 pages 8 figures paper prepared for IISC-2

Reaping the Rewards of Co-Operation. Franco-British Intelligence Sharing during the Gas War, 1915-1918

Based on British and French archive material, this paper seeks to contribute to the limited “coalition warfare historiography” by exploring a neglected but revealing aspect of Franco-British chemical warfare between 1915-1918: Intelligence sharing. A contextual overview of the two allied intelligence services prior to and following the outbreak of war highlights their complementary strength and global reach. The tactical and strategic significance of French and British intelligence failures at the time of the first German poison gas attacks in April 1915 is examined and contrasted with subsequent allied experience. The discussion focuses upon the two most productive sources of allied intelligence information, mainly reports from secret agents and enemy prisoner of war interview digests. The volume, quality and detail of this material, and its importance to the Franco-British gas war effort are underlined. The article demonstrates how closely and effectively the two allies co-operated by exploiting their shared intelligence data to successfully anticipate German initiatives and to mitigate the searching battlefield challenge posed by an enemy whose technological superiority and resource advantages were evident especially during the earlier periods of the gas war on the Western Front

Propagation des crises et comité d'audit

d'étudier l'influence des caractéristiques du comité d'audit sur la capacité des entreprises à résister à la crise boursière asiatique. La capacité de l'entreprise à résister à la crise est évaluée par la minimisation de la volatilité conditionnelle des rendements financiers estimée par les spécifications ARCH et GARCH. Sur un échantillon de 94 entreprises cotées et industrielles de quatre pays asiatiques: Malaisie, Thaïlande, Indonésie et Philippines et sur une période entière de la crise s'étalant de 1996 à 1998, nous parvenons à montrer que l'existence du comité d'audit, la taille et l'indépendance de ses membres constituent les attributs les plus importants du comité d'audit dans le contexte de la crise asiatique. Le nombre de rencontres annuelles serait sans effet sur la résistance à la crise.gouvernement d'entreprise, comité d'audit, propagation des crises, volatilité conditionnelle des rendements financiers.

Understanding face and eye visibility in front-facing cameras of smartphones used in the wild

Commodity mobile devices are now equipped with high-resolution front-facing cameras, allowing applications in biometrics (e.g., FaceID in the iPhone X), facial expression analysis, or gaze interaction. However, it is unknown how often users hold devices in a way that allows capturing their face or eyes, and how this impacts detection accuracy. We collected 25,726 in-the-wild photos, taken from the front-facing camera of smartphones as well as associated application usage logs. We found that the full face is visible about 29% of the time, and that in most cases the face is only partially visible. Furthermore, we identified an influence of users' current activity; for example, when watching videos, the eyes but not the entire face are visible 75% of the time in our dataset. We found that a state-of-the-art face detection algorithm performs poorly against photos taken from front-facing cameras. We discuss how these findings impact mobile applications that leverage face and eye detection, and derive practical implications to address state-of-the art's limitations

Evolution de la gouvernance des entreprises et impact sur la visibilité boursière en période de crise

Le passage de la sphère financière à la sphère réelle lors des crises économiques a pour conséquence un effet de dominos qui accélère la propagation des crises. Pourtant certaines entreprises résistent mieux que d'autres, limitant ainsi la propagation, et l'efficacité des pratiques de gouvernance est souvent avancée comme une des explications du phénomène. Dans la période 2006-2008 (avant et pendant la crise) on observe des changements notables dans les scores représentatifs de la gouvernance des entreprises. Nous parvenons à montrer que la plupart des entreprises montrent un degré de conformité assez satisfaisant avec les principes de l'OCDE. L'influence des scores de gouvernance sur la capacité des entreprises à absorber le choc de la crise est évaluée par la minimisation de la volatilité conditionnelle des rendements financiers estimée par les spécifications ARCH et GARCH. Les liens entre les différents scores de gouvernance et la volatilité conditionnelle des rendements financiers sont observés. Les bonnes pratiques de gouvernance, gages de confiance des actionnaires amélioreraient donc la visibilité de l'entreprise par le marché en période de crise.GOUVERNANCE; SCORE DE GOUVERNANCE; CRISE BOURSIERE; VOLATILITE CONDITIONNELLE DES RENDEMENTS FINANCIERS