Career Concerns of Top Executives, Managerial Ownership and CEO Succession

We model the portfolio decisions by managers with career concerns in a context where ownership of the firm's stock can affect the outcome of promotion contests. In addition to their utility from wealth, such managers derive utility from the monetary and non-monetary benefits (prestige) of running a corporation. Our theory predicts that top managers competing for the CEO position will distort their investment decisions away from the optimum portfolio choice in the absence of career concerns. Thus, our model suggests that changing career opportunities can explain portfolio decisions by managers and that insider ownership can help explain the outcomes of promotion contests. Our main testable predictions are that higher ownership by insiders increases their chances of being appointed CEO; that lower ownership by inside managers makes outside CEO appointments more likely; and that a lower probability of CEO turnover (and thus reduced promotion opportunities) leads inside managers to reduce their ownership in the firm and/or to leave the company. Using data on managerial ownership surrounding CEO turnover events, we find evidence supporting the predictions of our model. Overall, our main insight is that insider ownership, the outcome of promotion contests, the choice between inside and outside CEO replacements, and executive departure decisions are all related. Nous développons un modèle de choix de portefeuille des gestionnaires dans un environnement où leurs chances d'être promu PDG sont liées à leur actionnariat dans l'entreprise. Puisque les gestionnaires valorisent leur nomination potentielle au rang de PDG, nous prédisons que leur choix de portefeuille sera biaisé par rapport au choix qu'ils auraient fait en l'absence d'anticipations carriéristes. Notre modèle prédit que des changements dans les chances d'être promu expliquent les choix de portefeuille des gestionnaires. En particulier, nous montrons empiriquement qu'un plus grand actionnariat augmente la chance d'être promu au rang de PDG, réduit la chance qu'un gestionnaire externe à l'entreprise soit nommé. De plus, une réduction dans la possibilité d'être promu réduit l'actionnariat des gestionnaires ou induit leur départ. Nous testons les hypothèses découlant du modèle en utilisant les changements dans l'actionnariat des gestionnaire lors de la démission du PDG. Les hypothèses importantes du modèle sont confirmées.managerial compensation, CEO succession, corporate tournament, portfolio allocation, rémunération des dirigeants, changement de PDG, tournoi corporatif, choix de portefeuille

Shape of the spatial mode function of photons generated in noncollinear spontaneous parametric downconversion

We show experimentally how noncollinear geometries in spontaneous parametric downconversion induce ellipticity of the shape of the spatial mode function. The degree of ellipticity depends on the pump beam width, especially for highly focused beams. We also discuss the ellipticity induced by the spectrum of the pump beam

Diseño de una metodología para la gestión sostenible de los recursos en áreas marinas protegidas

La nueva Política Marina Integrada de la Unión Europea (UE) tiene como objetivo general la optimización y sostenibilidad de la explotación del mar. En este contexto, la figura de las Áreas Marinas Protegidas (AMPs) se plantea como un valioso instrumento para avanzar en la ordenación y gestión sostenible de los recursos marinos, permitiendo una gran variedad de alternativas en función del objetivo de conservación, el nivel de protección y las diferentes posibilidades de aprovechamiento de los recursos. Esta comunicación se centra en el diseño de una metodología de planificación que, incorporada al proceso de creación de un Área Marina Protegida (AMP), permita establecer una ordenación y gestión eficaz del espacio basada en el conocimiento, tanto de las características ambientales del medio marino, como de las presiones e impactos producidos por las actividades humanas. La metodología que se plantea, mediante instrumentos y herramientas de gestión concretas, permite definir objetivos específicos así como indicadores de seguimiento asociados, integrando en todas las fases del proceso a las organizaciones, grupos de interés e instituciones implicadas; de forma específica al sector pesquero, que ha de desempeñar un papel fundamental en el desarrollo de un nuevo modelo de conservación y gestión sostenible del medio marin

An algebraic approach to the minimum-cost multi-impulse orbit transfer problem

A purely algebraic formulation (i.e., polynomial equations only) of the minimum-cost multi-impulse orbit-transfer problem without time constraints is presented, while keeping all the variables with a precise physical meaning. General algebraic techniques are applied to solve these equations (resultants, Gröbner bases, etc.) in several situations of practical interest of different degrees of generality. For instance, a proof of the optimality of the Hohmann transfer for the minimum-fuel two-impulse circular-to-circular orbit-transfer problem is provided. Finally, a general formula is also provided for the optimal two-impulse in-plane transfer between two rotated elliptical orbits under a mild symmetry assumption on the two points where the impulses are applied (which, it is conjectured, can be removed)

Information fusion from multiple databases using meta-association rules

Nowadays, data volume, distribution, and volatility make it difficult to search global patterns by applying traditional Data Mining techniques. In the case of data in a distributed environment, sometimes a local analysis of each dataset separately is adequate but some other times a global decision is needed by the analysis of the entire data. Association rules discovering methods typically require a single uniform dataset and managing with the entire set of distributed data is not possible due to its size. To address the scenarios in which satisfying this requirement is not practical or even feasible, we propose a new method for fusing information, in the form of rules, extracted from multiple datasets. The proposed model produces meta-association rules, i.e. rules in which the antecedent or the consequent may contain rules as well, for finding joint correlations among trends found individually in each dataset. In this paper, we describe the formulation and the implementation of two alternative frameworks that obtain, respectively, crisp meta-rules and fuzzy meta-rules. We compare our proposal with the information obtained when the datasets are not separated, in order to see the main differences between traditional association rules and meta-association rules. We also compare crisp and fuzzy methods for meta-association rule mining, observing that the fuzzy approach offers several advantages: it is more accurate since it incorporates the strength or validity of the previous information, produces a more manageable set of rules for human inspection, and allows the incorporation of contextual information to the mining process expressed in a more human-friendly format

Anderson localization in a periodic photonic lattice with a disordered boundary

We investigate experimentally the light evolution inside a two-dimensional finite periodic array of weakly- coupled optical waveguides with a disordered boundary. For a completely localized initial condition away from the surface, we find that the disordered boundary induces an asymptotic localization in the bulk, centered around the initial position of the input beam.Comment: 3 pages, 4 figure

Charge reversal of colloidal particles

A theory is presented for the effective charge of colloidal particles in suspensions containing multivalent counterions. It is shown that if colloids are sufficiently strongly charged, the number of condensed multivalent counterion can exceed the bare colloidal charge leading to charge reversal. Charge renormalization in suspensions with multivalent counterions depends on a subtle interplay between the solvation energies of the multivalent counterions in the bulk and near the colloidal surface. We find that the effective charge is {\it not} a monotonically decreasing function of the multivalent salt concentration. Furthermore, contrary to the previous theories, it is found that except at very low concentrations, monovalent salt hinders the charge reversal. This conclusion is in agreement with the recent experiments and simulations

Experimental estimation of the dimension of classical and quantum systems

An overwhelming majority of experiments in classical and quantum physics make a priori assumptions about the dimension of the system under consideration. However, would it be possible to assess the dimension of a completely unknown system only from the results of measurements performed on it, without any extra assumption? The concept of a dimension witness answers this question, as it allows one to bound the dimension of an unknown classical or quantum system in a device-independent manner, that is, only from the statistics of measurements performed on it. Here, we report on the experimental demonstration of dimension witnesses in a prepare and measure scenario. We use pairs of photons entangled in both polarization and orbital angular momentum to generate ensembles of classical and quantum states of dimensions up to 4. We then use a dimension witness to certify their dimensionality as well as their quantum nature. Our results open new avenues for the device-independent estimation of unknown quantum systems and for applications in quantum information science.Comment: See also similar, independent and jointly submitted work of J. Ahrens et al., quant-ph/1111.127

PROGRESS REPORT Global Country Policy Review: A humanitarian comparative analysis on drug policies, on the basis of the Rome Consensus 2.0

This report advances our global understanding of drug policy by focusing on two key components: a bibliometric analysis and the creation of preliminary country profiles. We aim to identify trends, challenges, and opportunities within drug policy globally, emphasizing how these aspects can be better aligned with humanitarian principles, Rome Consensus 2.0, and Sustainable Development. Importantly, as the world has recognized the inability of the War on Drugs as a strategy to reduce drug use or drug-related crime, which is to say, to make us more safe and healthier (the two aims of the War on Drugs), this Project provides a new vision for where nations can go next that achieves the desired public safety and public health aspects all peoples want to see in their own communities and countries. Drawing from the preliminary insights, the report advocates for a more holistic and evidence-driven approach to drug policy. This entails broadening support for harm reduction, improving treatment services and the professional workforce, encouraging international collaboration to address the challenges of the transnational illicit drug trade, and reassessing policies that perpetuate stigma. Serving as an overview for the upcoming Global Policy Review (GPR), this report emphasizes the importance of drug policy frameworks that respect human dignity and contribute to achieving Sustainable Development Goals, with intentions to expand the review to more UN member states and provide bi-annual updates

Differential genetic interactions of yeast stress response MAPK pathways.

Genetic interaction screens have been applied with great success in several organisms to study gene function and the genetic architecture of the cell. However, most studies have been performed under optimal growth conditions even though many functional interactions are known to occur under specific cellular conditions. In this study, we have performed a large-scale genetic interaction analysis in Saccharomyces cerevisiae involving approximately 49 × 1,200 double mutants in the presence of five different stress conditions, including osmotic, oxidative and cell wall-altering stresses. This resulted in the generation of a differential E-MAP (or dE-MAP) comprising over 250,000 measurements of conditional interactions. We found an extensive number of conditional genetic interactions that recapitulate known stress-specific functional associations. Furthermore, we have also uncovered previously unrecognized roles involving the phosphatase regulator Bud14, the histone methylation complex COMPASS and membrane trafficking complexes in modulating the cell wall integrity pathway. Finally, the osmotic stress differential genetic interactions showed enrichment for genes coding for proteins with conditional changes in phosphorylation but not for genes with conditional changes in gene expression. This suggests that conditional genetic interactions are a powerful tool to dissect the functional importance of the different response mechanisms of the cell