On the Manipulability of Proportional Representation

This paper presents a new model of voter behaviour under methods of proportional representation (PR). We abstract away from rounding, and assume that a party securing k percent of the vote wins exactly k percent of the available seats. Under this assumption PR is not manipulable by any voter aiming at maximisation of the number of seats in the parliament of her most preferred party. However in this paper we assume that voters are concerned, first and foremost, with the distribution of power in the post-election parliament. We show that, irrespective of which positional scoring rule is adopted, there will always exist circumstances where a voter would have an incentive to vote insincerely. We demonstrate that a voter’s attitude toward uncertainty can influence her incentives to make an insincere vote. Finally, we show that the introduction of a threshold - a rule that a party must secure at least a certain percentage of the vote in order to reach parliament - creates new opportunities for strategic voting. We use the model to explain voter behaviour at the most recent New Zealand general election.

Évolution des profils d'état de santé et utilisation des services sociosanitaires chez les personnes âgées

Réalisé en cotutelle avec l'Université de Paris-Sud

A propos de l’actionnariat « détaché »

From a legal perspective, the membership in a business corporation is expressed through shares, and individual membership succession can in principle be achieved through a negotiable transaction. This has the effect that the interests of the corporation’s shareholders may be directed away from the enterprise activity to the shares, into which the corporation is divided. To illustrate this shift of interest, I characterize the membership in a business corporation as potentially “dispassionate”. Serving the financial interests of the “dispassionate” shareholder will be presented here as the modus operandi of the corporation. In this light, the attention that a company’s management must pay to the enrichment of shareholders depends on the importance of dispassionate shareholder support for the company’s activities. This perspective permits the introduction of new arguments in the CSR debate.

Conditions de vie des personnes âgées en Afrique Subsaharienne : cas de la vie dans un ménage à génération coupée au Niger

Comme dans la plupart des pays francophones d’Afrique Subsaharienne, la question du vieillissement ou la situation des personnes âgées ne sont pas encore d’actualité au Niger, principalement à cause de la jeunesse de sa population d’une part et d’un intérêt plus porté sur les enfants, les adolescents et les mères d’autre part. Pourtant le Niger fait face à une crise économique sans précédent qui peut avoir des conséquences néfastes sur les conditions de vie des personnes âgées. D’un côté, selon la coutume, la personne âgée (généralement grand parent) s’occupe principalement des petits enfants (orphelins ou non) qui lui sont confiés par leurs parents vivant dans la même localité ou ailleurs, ou qui sont décédés. De l’autre, l’absence d’un jeune adulte dans un ménage où vit au moins une personne âgée est considérée comme un phénomène social préoccupant dans les pays à forte prévalence de VIH/SIDA. Le Niger fait partie des pays où la proportion des personnes âgées vivant avec des petits enfants en l’absence de leurs parents adultes est la plus élevée. Cependant, malgré une forte mortalité adulte, l’absence de données fiables ne permet pas de le classer parmi les pays à forte mortalité adulte due au VIH/SIDA. La raison de cette situation est donc à chercher dans les différences individuelles et communautaires. Jusqu’au début des années 1990, la plupart des études sur les personnes âgées réalisées en Afrique Subsaharienne étaient basées sur les études qualitatives, tandis que les plus récentes sont faites à partir des données des recensements ou enquêtes sociodémoraphiques et économiques. Les conditions de vie des personnes âgées et les conséquences de la pauvreté et du VIH/SIDA sur celles-ci sont les principaux thèmes jusque-là couverts à l’aide des données existantes. Mais, il manque encore de données longitudinales essentielles à l’analyse de certains aspects du cycle de vie des personnes âgées. L’étude n’étant pas sociologique, c’est à l’aide de données démographiques quantitatives, plus précisément le recensement général de la population, que nous tenterons d’expliquer le phénomène sur une base exploratoire. L’analyse au niveau individuel a été faite à l’aide de la régression logistique sous STATA, tandis qu’au niveau contextuel, nous avons utilisé l’analyse multiniveau à l’aide du logiciel HLM (version 6.0). Les résultats indiquent que la vie en l’absence d’un jeune adulte et dans un ménage à génération coupée dépendent principalement du statut sociodémographique de la personne âgée au Niger. Par exemple, il ressort que le mariage avantage l’homme âgé, tandis que le veuvage l’isole plus que la femme âgée. Au niveau contextuel, ce sont les facteurs socioéconomiques qui influencent les conditions de vie des personnes âgées. L’étude montre, en effet, que le degré d’urbanisation d’une commune augmente le risque d’isolement d’une personne âgée qui y réside, alors que le niveau de pauvreté le réduit. Toutefois, nos résultats sont à prendre avec prudence parce qu’en premier lieu il n’existe pas d’études références sur le sujet tant au Niger que dans la sous-région d’Afrique francophone sahélienne. Ensuite, parce que le phénomène étudié pourrait être mesuré de plusieurs manières en fonction du contexte et des données disponibles, et que l’analyse approfondie des effets du statut matrimonial nécessiterait une plus grande connaissance du phénomène chez les personnes âgées. Enfin, compte tenu de la faible prévalence du VIH/SIDA au Niger, les principaux facteurs explicatifs de la vie dans un ménage à génération coupée (aussi bien pour les personnes âgées que pour les enfants) pourraient être le confiage des enfants ou la mortalité adulte due aux autres causes telles que le paludisme, la tuberculose et les maladies infectieuses. Toutefois, l’absence d’informations relatives à ces aspects dans les données utilisées n’a pas permis de les intégrer dans notre étude. Ainsi, compte tenu de la difficulté d’appréhender les contours du phénomène, les futurs programmes en faveur des personnes âgées au Niger et en Afrique Subsaharienne francophone doivent se baser sur des études concrètes relatives aux dimensions sociale et économique du phénomène. Mots clés : Niger - personnes âgées - conditions de vie - mode de vie - cohabitation intergénérationnelle - études comparatives - absence d’un jeune adulte - ménage à génération coupée - Afrique.

On-the-Fly Maintenance of Series-Parallel Relationships in Fork-Join Multithreaded Programs

A key capability of data-race detectors is to determine whether one thread executes logically in parallel with another or whether the threads must operate in series. This paper provides two algorithms, one serial and one parallel, to maintain series-parallel (SP) relationships "on the fly" for fork-join multithreaded programs. The serial SP-order algorithm runs in O(1) amortized time per operation. In contrast, the previously best algorithm requires a time per operation that is proportional to Tarjan’s functional inverse of Ackermann’s function. SP-order employs an order-maintenance data structure that allows us to implement a more efficient "English-Hebrew" labeling scheme than was used in earlier race detectors, which immediately yields an improved determinacy-race detector. In particular, any fork-join program running in T₁ time on a single processor can be checked on the fly for determinacy races in O(T₁) time. Corresponding improved bounds can also be obtained for more sophisticated data-race detectors, for example, those that use locks. By combining SP-order with Feng and Leiserson’s serial SP-bags algorithm, we obtain a parallel SP-maintenance algorithm, called SP-hybrid. Suppose that a fork-join program has n threads, T₁ work, and a critical-path length of T[subscript ∞]. When executed on P processors, we prove that SP-hybrid runs in O((T₁/P + PT[subscript ∞]) lg n) expected time. To understand this bound, consider that the original program obtains linear speed-up over a 1-processor execution when P = O(T₁/T[subscript ∞]). In contrast, SP-hybrid obtains linear speed-up when P = O(√T₁/T[subscript ∞]), but the work is increased by a factor of O(lg n).

La mora accipendi en el derecho del trabajo colombiano

El contrato de trabajo es fuente de diversas obligaciones para las partes involucradas en él: empleador y trabajador. El trabajador debe prestar los servicios personales encomendados y el empleador debe pagar el salario como obligaciones principales. Sin embargo, en ocasiones de crisis económica, como la que vivimos, se verifican supuestos en que resulta imposible para el trabajador cumplir con sus obligaciones principales por causas imputables al acreedor (empleador), contexto en el cual nos adentramos en la problemática que abordaremos: la mora del acreedor en el contrato de trabajo.

Works Councils: An Agency Perspective

This paper investigates the role of works councils in a simple agency framework in whichworks councils are supposed to monitor manager's information on behalf of the workforce,but they are independent agents who might pursue their private interest. First, we considerthat workers can incentivize works councils through contingent monetary payments. In orderto deter collusion, workers must pay higher compensations in states of nature where they canbe expropriated by potential coalitions among works councils and management. Collusionmakes contingent payments costly and reduces workers' payoffs. Second, when elections areused to align works councils' interest only well compensated representatives would face aninter-temporal trade-off between accepting management's transfers at first period and losingrents at the second period. Elections increase the cost of entering on collusive behaviour withmanagement and works councils will try to behave on the employees' interest.

Works councils: an agency perspective

This paper investigates the role of works councils in a simple agency framework in which works councils are supposed to monitor manager’s information on behalf of the workforce, but they are independent agents who might pursue their private interest. First, we consider that workers can incentivize works councils through contingent monetary payments. In order to deter collusion, workers must pay higher compensations in states of nature where they can be expropriated by potential coalitions among works councils and management. Collusion makes contingent payments costly and reduces workers’ payoffs. Second, when elections are the exclusive mechanisms to align works councils’ interest, only well compensated representatives would face an intertemporal tradeoff between accepting management’s transfers at first period and losing rents at the second period. Elections increase the cost of entering on collusive behavior with management and works councils will try to behave on the employees’ interest.

Sentencia de la Corte Constitucional del Ecuador sobre la constitucionalidad de la obligación del afianzamiento tributario (Jurisprudencia)

Los sujetos pasivos que impugnen ante la vía judicial un acto administrativo mediante el cual se pretenda determinar o recaudar tributos, deben rendir una caución equivalente al 10% de la cuantía de su demanda, de no presentársela en el término de quince días, el acto impugnado queda ejecutoriado y los jueces deben ordenar el archivo del proceso. Nuestra Corte Constitucional para el Período de Transición considera que no se vulnera derecho alguno en ese caso, siempre y cuando se exija rendir la caución después de calificada la demanda. Estudiaremos los fundamentos que tuvo la Corte Constitucional para llegar a esa conclusión. Pretenderemos analizarlos y cuestionarlos objetivamente, para así demostrar por qué su falta de coherencia y de sustento permite concluir que su análisis pecó por falto de imparcialidad, y por qué es razonable suponer que sus móviles no fueron jurídicos en lo absoluto, sin perjuicio de que, a la par, demos nuestro parecer al respecto. Independientemente de la trascendencia jurídica que puedan o no tener en nuestro ordenamiento, esperamos se entienda por qué creemos que estos precedentes deben ser considerados como un capítulo funesto en la historia de la jurisprudencia constitucional ecuatoriana.

Asymmetric output gap effects in Phillips Curve and mark-up pricing models: evidence for the US and the UK

A number of studies have found an asymmetric response of consumer price index inflation to the output gap in the US in simple Phillips curve models. We consider whether there are similar asymmetries in mark-up pricing models, that is, whether the mark-up over producers' costs also depends upon the sign of the (adjusted) output gap. The robustness of our findings to the price series is assessed, and also whether price-output responses in the UK are asymmetric.

A ictiofauna agregada a um sistema de piscicultura em tanques-rede na represa oligotrófica de Chavantes (médio rio Paranapanema, SP/PR): composição de espécies e atributos ecológicos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Opinião de familiares sobre a internação de crianças em uma Unidade de Terapia Intensiva Pediátrica

A Pediatric Intensive care Unit (PICU) is an environment where care is provided to seriously ill children. Hospitalization is regarded as an unpleasant experience that requires adaptation and routine change. To assess the opinion of relatives of children hospitalized at a PICU concerning tie breakage and/or separation between children and their families. It is a descriptive, cross-sectional, quantitative study. A structured interview was conducted with the families of hospitalized children from July to September, 2010. The data were statistically analyzed. RESULTS: Twenty relatives were interviewed, 80% of whom believed that children’s behavior changes when they are present in the unit, and 85% considered the visitation time established to be sufficient. All the respondents reported to be satisfied about the care provided. The feelings prevailing in 50% of the relatives were fear and hope. Change in the family’s union after hospitalization occurred in 85% of the families. The most fearful aspect concerning the ICU is the equipment (25%), and the most worrisome, as regards personal life, is the separation from other children (65%). Health care professionals must pay more attention to relatives by including them in their health care plan so that the health care team and the family, who are essential in children’s recovery, can interact in a congenial fashion. It is also necessary to improve the knowledge related to that subject so that the health care team and families can work together towards children’s recovery

Transtorno mental comum nos estudantes de medicina da Faculdade de Medicina de Botucatu-UNESP: uma análise longitudinal

Pós-graduação em Saúde Coletiva - FMB

Análises energética e econômica da produção de leitões de produtores familiares do Oeste do Paraná

The present study aimed to analyze indicators of energy efficiency and economic production of piglets from family farmers in Paraná. We sought to determine possible differences in energy efficiencies and economic producers who manufactured rations on their property and those who bought rations Cooperative. The sample was obtained by accessibility (six producers who manufactured and six who bought rations) and not probabilistic, and the raw data were transformed into energy and economic units, and processed in electronic spreadsheets. The two production systems of piglets in the nursery phase, family farming, showed negative energy balance, with energy inputs higher than outputs. The two systems of rearing piglets showed no differences in energy efficiency, ie, they were not self-sufficient and needed to import energy sources from other systems. The indicators of economic efficiency of producers who buy rations as those who produce them in their properties were less than unity. Thus, most producers did not generate enough revenue to pay the costs in the short term and lost money.

Fixed and Flexible: Coexistence of Obligate and Facultative Migratory Strategies in a Freshwater Fish

Migration is an important event in many animal life histories, but the degree to which individual animals participate in seasonal migrations often varies within populations. The powerful ecological and evolutionary consequences of such partial migration are now well documented, but the underlying mechanisms are still heavily debated. One potential mechanism of partial migration is between-individual variation in body condition, where animals in poor condition cannot pay the costs of migration and hence adopt a resident strategy. However, underlying intrinsic traits may overrule such environmental influence, dictating individual consistency in migratory patterns. Unfortunately, field tests of individual consistency compared to the importance of individual condition on migratory propensity are rare. Here we analyse 6 years of field data on roach migration, gathered by tagging almost 3000 individual fish and monitoring their seasonal migrations over extended periods of time. Our aims were to provide a field test of the role of condition in wild fish for migratory decisions, and also to assess individual consistency in migratory tendency. Our analyses reveal that (1) migratory strategy, in terms of migration/residency, is highly consistent within individuals over time and (2) there is a positive relationship between condition and the probability of migration, but only in individuals that adopt a migratory strategy at some point during their lives. However, life-long residents do not differ in condition to migrants, hence body condition is only a good predictor of migratory tendency in fish with migratory phenotypes and not a more general determinant of migratory tendency for the population. As resident individuals can achieve very high body condition and still remain resident, we suggest that our data provides some of the first field evidence to show that both facultative and obligate strategies can co-exist within populations of migratory animals.