[hal-01343348] D.1.3 – Protocols for emergent localities

This report presents two contributions that illustrate the potential of emerging-locality protocols in large-scale decentralized systems, in two areas of decentralized social computing: recommendation, and eventual consistency of mutable data structures. The first contribution consists of a framework supporting the development of dynamically adaptive decen-tralised recommendation systems. Decentralised recommenders have been proposed to deliver privacy-preserving, personalised and highly scalable on-line recommendations. Current implementations tend, however, to rely on a hard-wired similarity metric that cannot adapt. This constitutes a strong limitation in the face of evolving needs. Our framework address this through a decentralised form of adaptation, in which individual nodes can independently select, and update their own recommendation algorithm, while still collectively contributing to the overall system's mission. Our second contribution addresses the growing demand for differentiated consistency requirements in large-scale applications. A large number of today's applications rely on Eventual Consistency, a consistency model that emphasizes liveness over safety. Designers generally adopt this consistency model uniformly throughout a distributed system due to its ability to scale as the number of users or devices grows larger. But this clashes with the need for differentiated consistency requirements. In this contribution, we address this need by introducing UPS, a novel consistency mechanism that offers differentiated eventual consistency and delivery speed by working in pair with a two-phase epidemic broadcast protocol. We propose a closed-form analysis of our approach's delivery speed, and we evaluate our complete protocol experimentally on a simulated network of one million nodes. To measure the consistency trade-off, we formally define a novel and scalable consistency metric operating at runtime.

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[hal-01316014] A Methodology for Quality Assessment in Collaborative Score Libraries

We examine quality issues raised by the development of XML-based Digital Score Libraries. Based on the authors' practical experience, the paper exposes the quality shortcomings inherent to the complexity of music encoding, and the lack of support from state-of-the-art formats. We also identify the various facets of the ``quality'' concept with respect to usages and motivations. We finally propose a general methodology to introduce quality management as a first-level concern in the management of score collections, and an initial taxonomy of quality problems based on real use cases.

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[hal-01343121] Impact de la recherche d'amorces mutées sur les résultats d'analyses métagénomiques

En métagénomique ciblée, une problématique récurrente concerne la quantité de lectures réellement exploitables en sortie d'un séquenceur à haut débit. L'une des étapes influençant cette quantité est la détection dans chaque séquence des amorces utilisées pour amplifier le gène ciblé. Usuellement les séquences n’ayant pas les amorces parfaites sont rejetées. Notre étude interroge l’impact d’accepter également les séquences avec amorces mutées. Il s’agit de répondre aux questions suivantes : Accepter les séquences avec amorces mutées permet-il d'augmenter le nombre de séquences exploitables par échantillon ? Cette augmentation impacte-t-elle les résultats obtenus au terme de l'analyse métagénomique , c’est-à-dire permet-elle d’augmenter le nombre d’OTU (Operationnal taxonomic unit), et donc potentiellement d’espèces, détectés ? L’étude a été menée sur 9 échantillons, dans le cadre d’une étude de la biodiversité des sols tropicaux chez les eucaryotes unicellulaires. Les échantillons ont été séquencés à la fois en Roche/454 et en Illumina MiSeq, afin de pouvoir constater l'impact de la technologie sur les résultats. Le séquençage a ciblé la région V4 de la sous-unité 18S de l'ARN ribosomique. En résultat, on observe que la recherche des amorces V4F et V4R mutées permet d'améliorer de façon non-négligeable la sensibilité de l’analyse métagénomique. Cela augmente le rappel parmi les séquences d'un échantillon et cela permet également la détection de nouveaux OTU (+7 à +10 %, dans notre étude, en fonction de la technologie de séquençage), que ce soit en augmentant l'abondance de séquences détectées en nombre insuffisant pour être validées ou que ce soit en détectant des séquences totalement nouvelles qui n'étaient pas visibles auparavant. Une étude supplémentaire a par ailleurs montré que ces nouveaux OTU, et notamment les totalement nouveaux, étaient aussi crédibles que les OTU avec amorces exactes.

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[hal-01313749] Temperature dependence of the particle/gas partition coefficient: An application to predict indoor gas-phase concentrations of semi-volatile organic compounds

The indoor gas-phase concentrations of semi-volatile organic compounds (SVOCs) can be predicted from their respective concentrations in airborne particles by applying the particle/gas partitioning equilibrium. The temperature used for partitioning is often set to 25 °C. However, indoor temperatures frequently differ from this reference value. This assumption may result in errors in the predicted equilibrium gas-phase SVOC concentrations. To improve the prediction model, the temperature dependence of the particle/gas partition coefficient must be addressed. In this paper, a theoretical relationship between the particle/gas partition coefficient and temperature was developed based on the SVOC absorptive mechanism. The SVOC particle/gas partition coefficients predicted by employing the derived theoretical relationship agree well with the experimental data retrieved from the literature (R > 0.93). The influence of temperature on the equilibrium gas-phase SVOC concentration was quantified by a dimensionless analysis of the derived relationship between the SVOC particle/gas partition coefficient and temperature. The predicted equilibrium gas-phase SVOC concentration decreased by between 31% and 53% when the temperature was lowered by 6 °C, while it increased by up to 750% when the indoor temperature increased from 15 °C to 30 °C

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[hal-01308004] Impact of the French 3rd and 4th generation pill scare in women seeking termination of pregnancy

Introduction The aim of this study was to evaluate changes in the contraceptive profile of women seeking termination of pregnancy following the debate on 3rd and 4th generation pills in France in 2012. Materials and methods Single-center case-control study comparing the attitude to contraception before (between 02/15/2012 and 07/16/2012) and after the debate (between 02/25/2013 and 06/24/2013). Results A total of 291 patients consulted before and 601 after the debate. We showed that there were more students (+9.5%), more single women (+8.3%) and fewer working women (–7.7%) in the cohort after the debate. After the termination procedure, prescriptions for long-acting reversible contraceptive (LARC) methods increased (+7.8%, P = 0.03), in particular in patients aged 25 or younger, including nulliparous (+12.6%, P = 0.02). Conclusion The media alert about the pill led to a change in the contraceptive standard in the post-abortion period and altered patient profiles. An increase was notably observed in certain vulnerable populations (high school students, unemployed and single women). It remains to be seen whether these changes are transient or permanent

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[hal-01290932] An Extension of SPARQL with Fuzzy Navigational Capabilities for Querying Fuzzy RDF Data

The Resource Description Framework (RDF) is the graph-based standard data model for representing semantic web information, and SPARQL is the standard query language for querying RDF data. Because of the huge volume of linked open data published on the web, these standards have aroused a large interest in the last years. This paper proposes a fuzzy extension of the SPARQL language that improves its expressiveness and usability. This extension allows (1) to query a fuzzy RDF data model, and (2) to express fuzzy preferences on data and on the structure of the data graph, which has not been proposed in any previous fuzzy extensions of SPARQL.

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[hal-01343753] Frederic Lee and post-Keynesian pricing theory

Frederic Lee has been a major contributor to post-Keynesian economics, mainly to its theory of pricing. This article summarizes his objections to the neoclassical view of the firm and pricing, as well as his view that changes in quantities, rather than in prices, provide the important information to firms. It also outlines Lee's views on competition, and examines the three pricing doctrines Lee carefully analyzed—markup pricing (associated with Kalecki), normal-cost pricing or full-cost pricing (associated with Andrews), and target-return or administered pricing (associated with Means). The article then discusses the relationship between Lee and three strands of post-Keynesianism: Kaleckian, Sraffian and Eichnerian pricing theories. It explains why Lee objected to some features of each of these. The article concludes by discussing why, towards the end of his life, Lee felt (mistakenly) that his ideas had been dismissed by heterodox economists.

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[hal-01343731] Ecological monetary economics: a post-Keynesian critique

The monetary analysis of some ecological economists currently appears to be mostly articulated around the following core: a stationary economy (and a fortiori a degrowth economy) is incompatible with a system in which money is created as interest-bearing debt. To question the relevance of the debt-money/positive interest rate/output growth nexus, this paper adopts a critical stance towards the currently emerging ecological monetary economics from the standpoint of another strand of heterodox economics – the post-Keynesian approach. In its current state, ecological monetary economics is at odds with post-Keynesian economics in its analysis of the money–growth relationship. This will be shown using the theory of endogenous money and a simple Cambridgian–Kaleckian model where debt-money and a positive interest rate are compatible with a full stationary economy.

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[hal-01343736] Teaching monetary theory and monetary policy implementation after the crisis

The author reflects on the state of macroeconomic theory, and more specifically on how monetary economics is being taught in the aftermath of the global financial crisis. Whereas heterodox macroeconomic theory is very much alive due to the influx of a large number of contributions and contributors, the latter still have a hard time finding positions in the academic world, as journal and departmental ranking exercises have restricted so-called standards of excellence to the neoclassical approach. The crisis has not yet induced mainstream economists to open up to different approaches that put more emphasis on realistic features than on imaginary ones based on neoclassical micro-foundations. As an exemplar, the chapters on money and banking in two first-year textbooks are being examined, an orthodox one by Greg Mankiw and a heterodox one by Neva Goodwin et al. Unsurprisingly there is little to be learned about the crisis from Mankiw's book, while the book by Goodwin et al. devotes a large amount of space to the causes and consequences of the crisis. Still, Goodwin and her co-authors are not heterodox enough: they are less heterodox than a number of central bankers when it comes to a number of key features of monetary theory.

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[hal-01343732] Convergence towards the normal rate of capacity utilization in neo-Kaleckian models: the role of non-capacity creating autonomous expenditures

Neo-Kaleckian models of growth and distribution have been highly popular among heterodox economists. Two drawbacks of these models have, however, been underlined in the literature: first, the models do not usually converge to their normal rate of capacity utilization; second, the models do not include the Harrodian principle of dynamic instability. Some Sraffian economists have long been arguing that the presence of non-capacity creating autonomous expenditures provides a mechanism that brings back the model to normal rates of capacity utilization, while safeguarding the main Keynesian message and without going back to classical conclusions. The present article provides a very simple proof of this, showing within a neo-Kaleckian model that the Harrodian principle of dynamic instability gets tamed by the presence of autonomous consumer expenditures.

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[hal-01343730] Peut-on expliquer le faible taux d'emploi des seniors en France ?

[...]

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[hal-01343728] Faut-il reculer l'âge légal du départ à la retraite ?

[...]

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[hal-01343744] The monetary and fiscal nexus of neo-chartalism: A friendly critique

A number of post-Keynesian authors, called the neo-chartalists, have argued that the government does not face a budget constraint similar to that of households and that government with sovereign currencies run no risk of default, even with high debt-to-GDP ratio. This stands in contrast to countries in the eurozone, where the central bank does not normally purchase sovereign debt. While these claims now seem to be accepted by some economists, neo-chartalists have also made a number of controversial claims, including that the government spends simply by crediting a private-sector-bank account at the central bank; that the government does need to borrow to deficit-spend; and that taxes do not finance government expenditures. This paper shows that these surprising statements do have some logic, once one assumes the consolidation of the government sector and the central bank into a unique entity, the state. The paper further argues, however, that these paradoxical claims end up being counter-productive since consolidation is counter-factual.

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[hal-01343745] Crise financière, répartition des revenus et relance par les salaires

Tandis que la plupart des économistes attribuent la crise financière de 2007-2008 aux incohérences des marchés financiers, un certain nombre d’économistes, surtout hétérodoxes, associent cette crise à des éléments structurels, notamment la croissance des inégalités, mesurée par la progression de la part des profits dans le revenu national et par la dispersion des salaires. L’auteur présente les résultats d’un projet de recherche dont les différents modules ont analysé les causes de ces évolutions ainsi que les conséquences négatives de la baisse de la part des salaires pour la croissance de la demande et la croissance de la productivité. Les politiques néolibérales ont donc eu des effets néfastes pour l’économie, effets qui n’ont pu être compensés que temporairement par des artifices comme l’endettement accru des ménages et les politiques de croissance par les exportations. Il importe donc de faire marche arrière, et de revenir à des politiques favorisant le plein emploi et la relance par les salaires.

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[hal-01343735] Understanding of the Global Financial Crisis: Contributions of post-Keynesian economics

Post-Keynesian economics has greatly improved our understanding of the causes as well as some of the consequences of the Global Financial Crisis. This paper deals with some examples related to monetary issues—namely, the financial instability hypothesis of Minsky and its extension to the household sector, as well as the post-Keynesian theory of endogenous money, with its extension to quantitative easing policies set within a framework where the central bank’s target rate of interest is set equal to the rate of interest paid on reserves.

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[hal-01343734] Linear and nonlinear Granger causality between short-term and long-term interest rates during business cycles

This paper is about the causal relationship between short-term and long-term interest rates in the U.S. and Canada. To that end, we apply a linear Granger causality test introduced by Toda-Yamamoto (1995) and the nonlinear Granger causality test of Diks and Panchenko (2006). By combining linear causality effects with the nonlinear ones, it is seen that the most common Granger causality direction between short-term and long-term interest rates is a bidirectional one. We also find that nonlinear Granger causality can be found where no linear causality had been uncovered. Moreover, our findings show that during recent business cycles, the federal funds rate (in the U.S.) and the overnight rate (in Canada) still Granger-cause long-term interest rates significantly.

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[hal-01343733] A two-sector model with target-return pricing in a stock-flow consistent framework

In this paper, we build a generalized Kaleckian two-sector model in a closed economy and explore the dynamics towards long-run positions. The model incorporates conflicting claims of labour and firms over income distribution and endogenous labour-saving technical progress. Adopting a stock-flow consistent framework, our simulation experiments yield the following results. First, the ‘paradox of thrift’ and the ‘paradox of costs’ hold, but the magnitude of the impact depends on the initial status of income distribution and monetary policy. Second, changes in autonomous labour-saving innovation might explain the phenomenon of the “new economy” of the second half of the 1990s within an alternative framework. Our model reinforces a post-Keynesian growth theory where aggregate demand is the crucial determinant of long-run positions as well as short-run positions, and shows that economic growth is demand-led and characterized by ‘path-dependency’.

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[hal-01343742] The Eurozone crisis: a balance-of-payment problem or a crisis due to a flawed monetary design?

Both Sergio Cesaratto and I see several flaws in the setup of the common currency Eurozone, and we both understand, in a similar way, the functioning of a monetary economy. The only point of disagreement it seems to me is that Cesaratto insists that the Eurozone crisis is a balance-of-payments problem, tied to current account deficits and capital outflows. But whereas the continuous loss of foreign reserves must eventually lead to some painful adjustment, Eurozone countries can never run out of TARGET2 balances, which can take unlimited negative values, so that the evolution of the balance of payments cannot be the source of the crisis. My view, and Roberto Frenkel’s, is that investors perceived, in contrast to other central banks, that the European Central Bank by convention and by design would decline to act as the purchaser of last resort until it became too late, which explains the speculative attacks against the securities issued by the governments of the Eurozone periphery.

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[hal-01343743] A comment on Endogenous money and effective demand: a revolution or a step backward?

Steve Keen argues that post-Keynesians have not sufficiently emphasized the revolutionary character of endogenous money for macroeconomic theory, and that this should be done by recognizing that aggregate demand is equal to current or past income plus the change in debt. This equation, attributed in particular to Hyman Minsky, is discussed and questioned, and it is recalled that a similar equation had been proposed by Alfred Eichner. The consequences of bank credit for firms or households are further analysed within the context of the national accounts, and it is shown that one does not need a redefinition of aggregate demand and aggregate supply, in contrast to what is proposed by Keen.

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[hal-01305478] Prenatal stress and early-life exposure to fluoxetine have enduring effects on anxiety and hippocampal BDNF gene expression in adult male offspring

With the growing use of selective serotonin reuptake inhibitor medications (SSRIs) for the treatment of depression during the perinatal period, questions have been raised about the longterm impact of these medications on development. We aimed to investigate how developmental SSRI exposure may alter affect-related behaviors and associated molecular processes in offspring using a rodent model of maternal stress and depression. For this purpose, prenatally stressed or non-stressed male offspring were exposed to fluoxetine (5 mg/kg/day) or vehicle, via lactation, until weaning. Primary results show that postnatal fluoxetine exposure differentially altered anxiety-like behavior by increasing anxiety in non-stressed offspring and decreasing anxiety in prenatally stressed offspring. In the hippocampus, developmental fluoxetine exposure decreased BDNF IV and TrkB mRNA expression. Prenatal stress alone also decreased escape behaviors and decreased hippocampal BDNF IV mRNA expression. These data provide important evidence for the long-term programming effects of early-life exposure to SSRIs on brain and behavior.

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