Statistical modeling of bowing control applied to violin sound synthesis

Excitation-continuous music instrument control patterns are often not explicitly represented in current sound synthesis techniques when applied to automatic performance. Both physical model-based and sample-based synthesis paradigmswould benefit from a flexible and accurate instrument control model, enabling the improvement of naturalness and realism. Wepresent a framework for modeling bowing control parameters inviolin performance. Nearly non-intrusive sensing techniques allow for accurate acquisition of relevant timbre-related bowing control parameter signals.We model the temporal contour of bow velocity, bow pressing force, and bow-bridge distance as sequences of short Bézier cubic curve segments. Considering different articulations, dynamics, and performance contexts, a number of note classes are defined. Contours of bowing parameters in a performance database are analyzed at note-level by following a predefined grammar that dictates characteristics of curve segment sequences for each of the classes in consideration. As a result, contour analysis of bowing parameters of each note yields an optimal representation vector that is sufficient for reconstructing original contours with significant fidelity. From the resulting representation vectors, we construct a statistical model based on Gaussian mixtures suitable for both the analysis and synthesis of bowing parameter contours. By using the estimated models, synthetic contours can be generated through a bow planning algorithm able to reproduce possible constraints caused by the finite length of the bow. Rendered contours are successfully used in two preliminary synthesis frameworks: digital waveguide-based bowed stringphysical modeling and sample-based spectral-domain synthesis.

Testing the descriptive performance of the rank-dependent utility in the domain of health profiles

Expected utility theory (EUT) has been challenged as a descriptive theoryin many contexts. The medical decision analysis context is not an exception.Several researchers have suggested that rank dependent utility theory (RDUT)may accurately describe how people evaluate alternative medical treatments.Recent research in this domain has addressed a relevant feature of RDU models-probability weighting-but to date no direct test of this theoryhas been made. This paper provides a test of the main axiomatic differencebetween EUT and RDUT when health profiles are used as outcomes of riskytreatments. Overall, EU best described the data. However, evidence on theediting and cancellation operation hypothesized in Prospect Theory andCumulative Prospect Theory was apparent in our study. we found that RDUoutperformed EU in the presentation of the risky treatment pairs in whichthe common outcome was not obvious. The influence of framing effects onthe performance of RDU and their importance as a topic for future researchis discussed.

Corporate governance and corporate social performance

By integrating the agency and stakeholder perspectives, this study aims to provide a systematic understanding of the firm- and institutional-level corporate governance factors that affect corporate social performance (CSP). We analyze a large global panel dataset and reveal that CSP is positively associated with board independence, but negatively with ownership concentration. These results underscore the idea that the benefits of CSP do not flow to shareholders to the same extent as the costs and that the allocation of resources to CSP is lower when shareholders are powerful. Furthermore, these findings indicate that independent directors should be understood as agents in their own right, not only focused on defending shareholder interests. We also find that CSP is negatively related to investor protection and shareholder-oriented environments, while it is positively related to egalitarian environments. Finally, we jointly analyze firm-level drivers and institutional contexts.

Agreement in interpersonal perception as a predictor of group performance

The present work deals with quantifying group characteristics. Specifically, dyadic measures of interpersonal perceptions were used to forecast group performance. 46 groups of students, 24 of four and 22 of five people, were studied in a real educational assignment context and marks were gathered as an indicator of group performance. Our results show that dyadic measures of interpersonal perceptions account for final marks. By means of linear regression analysis 85% and 85.6% of group performance was respectively explained for group sizes equal to four and five. Results found in the scientific literature based on the individualistic approach are no larger than 18%. The results of the present study support the utility of dyadic approaches for predicting group performance in social contexts.

Measuring sustained superior performance at the firm level

This paper proposes a two-dimensional Strategic Performance Measure (SPM) to evaluate the achievement of sustained superior performance. This proposal builds primarily on the fact that, under the strategic management perspective, a firm's prevalent objective is the pursuit of sustained superior performance. Three basic conceptual dimensions stem from this objective: relativity, sign dependence, and dynamism. These are the foundations of the SPM, which carries out a separate evaluation of the attained superior performance and of its sustainability over time. In contrast to existing measures of performance, the SPM provides: (i) a dynamic approach by considering the progress or regress in performance over time, and (ii) a cardinal measurement of performance differences and its changes over time. The paper also proposes an axiomatic framework that a measure of strategic performance should comply with to be theoretically and managerially sound. Finally, an empirical illustration of the Spanish banking sector during 1987-1999 is herein provided by discussing some relevant cases.

Single period Markowitz portfolio selection, performance gauging and duality: a variation on Luenberger's shortage function

Markowitz portfolio theory (1952) has induced research into the efficiency of portfolio management. This paper studies existing nonparametric efficiency measurement approaches for single period portfolio selection from a theoretical perspective and generalises currently used efficiency measures into the full mean-variance space. Therefore, we introduce the efficiency improvement possibility function (a variation on the shortage function), study its axiomatic properties in the context of Markowitz efficient frontier, and establish a link to the indirect mean-variance utility function. This framework allows distinguishing between portfolio efficiency and allocative efficiency. Furthermore, it permits retrieving information about the revealed risk aversion of investors. The efficiency improvement possibility function thus provides a more general framework for gauging the efficiency of portfolio management using nonparametric frontier envelopment methods based on quadratic optimisation.

The Effect of relationship lending on firm performance

We examine how relationship lending affects firm performance using a panel dataset of about 70,000 small and medium Spanish firms in the period 1993-2004. We model firm performance jointly with the firm's choice of the number of bank relationships. Controlling for firm fixed effects and using instrumental variables for the decision on the number of bank relationships, we find that firms maintaining exclusive bank relationships have lower profitability. The result is consistent with the view that banks appropriate most of the value generated through close relationships with its borrowers as long as they do not face competition from other lenders.

Publishing performance of spanish academics: 1970-2004: institutions, researchers et al.

This work complements some of the results appearing in the article ?Publishing Performance in Economics: Spanish Rankings? by Dolado et al. . Specifically we focus on the robustness of the results regardless of the time span considered, the effect of the choice of a particular database on the final results, and the effects on changes in the unit of institutional measure (departments versus institutions as a whole). Differences are significant when we expand the time period considered. There are also significant but small differences if we combine datasets to derive the rankings. Finally, department rankings offer a more precise picture of the situation of the Spanish academics, although results do not differ substantially from those obtained when overall institutions are considered.

El Impacto de la gestión activa en la performance de los fondos de inversión de renta fija

Este trabajo tiene como objetivo estudiar el impacto de las estrategias activas de gestión en la performance de los fondos de inversión de renta fija y se realiza en tres fases, en primer lugar, a partir de la información homogénea disponible para cualquier partícipe se elabora un perfil de riesgo de los fondos a partir de los tipos de riesgo asociados a la renta fija. En segundo lugar, se propone una medida de performance que permite la comparación entre fondos, a dos niveles: por un lado, tomando como benchmark una cartera puramente pasiva y por otro lado, adecuando el benchmark al vencimiento de la cartera. En tercer lugar se realiza un contraste con el fin de determinar el impacto en la performance de los fondos estudiados de los indicadores de actividad de la estrategia asociados al perfil de riesgo del fondo.

La performance teatral del juglar contemporani Matteo Belli

En aquesta dissertació he intentat recórrer els principals elements que caracteritzen el treball teatral de l’actor contemporani bolonyès Matteo Belli. La primera part se centra en les informacions bàsiques, necessàries per col•locar correctament el fenòmen tan complex com fascinant del joglar. En segona instància, he pensat en aprofundir l’aspecte de la comicitat introduint directament el treball de Belli, i relacionar-lo, per dir-ho així, amb el panorama actual del teatre contemporani. A més a més, he presentat alguns exemples relacionats amb algunes obres d’artistes moderns i contemporanis italians, d’aquesta manera prentenc comprendre millor el procés de voluntarietat que s’amaga darrere la comicitat i els seus mecanismes intrínsecs. Per concloure, he inclòs una entrevista amb ell, que em va concedir en aquests quatre anys de recerca, on es pot apreciar, no només un gran coneixement del món de l’espectacle, sinó que també una profunda espessor cultural.

Evaluating the impact of public subsidies on a firm's performance: A quasi-experimental approach

Many regional governments in developed countries design programs to improve the competitiveness of local firms. In this paper, we evaluate the effectiveness of public programs whose aim is to enhance the performance of firms located in Catalonia (Spain). We compare the performance of publicly subsidised companies (treated) with that of similar, but unsubsidised companies (non-treated). We use the Propensity Score Matching (PSM) methodology to construct a control group which, with respect to its observable characteristics, is as similar as possible to the treated group, and that allows us to identify firms which retain the same propensity to receive public subsidies. Once a valid comparison group has been established, we compare the respective performance of each firm. As a result, we find that recipient firms, on average, change their business practices, improve their performance, and increase their value added as a direct result of public subsidy programs.

Comparing the early research performance of PhD graduates in labor economics in Europe and the USA

This paper analyzes the early research performance of PhD graduates in labor economics, addressing the following questions: Are there major productivity differences between graduates from American and European institutions? If so, how relevant is the quality of the training received (i.e. ranking of institution and supervisor) and the research environment in the subsequent job placement institution? The population under study consists of labor economics PhD graduates who received their degree in the years 2000 to 2005 in Europe or the USA. Research productivity is evaluated alternatively as the number of publications or the quality-adjusted number of publications of an individual. When restricting the analysis to the number of publications, results suggest a higher productivity by graduates from European universities than from USA universities, but this difference vanishes when accounting for the quality of the publication. The results also indicate that graduates placed at American institutions, in particular top ones, are likely to publish more quality-adjusted articles than their European counterparts. This may be because, when hired, they already have several good acceptances or because of more focused research efforts and clearer career incentives.