Firm entry, inflation and the monetary transmission mechanism

This paper estimates a business cycle model with endogenous firm entry by matching impulse responses to a monetary policy shock in US data. Our VAR includes net business formation, profits and markups. We evaluate two channels through which entry may influence the monetary transmission process. Through the competition effect, the arrival of new entrants makes the demand for existing goods more elastic, and thus lowers desired markups and prices. Through the variety effect, increased firm and product entry raises consumption utility and thereby lowers the cost of living. This implies higher markups and, through the New Keynesian Phillips Curve, lower inflation. While the proposed model does a good job at matching the observed dynamics, it generates insufficient volatility of markups and profits. Estimates of standard parameters are largely unaffected by the introduction of firm entry. Our results lend support to the variety effect; however, we find no evidence for the competition effect.entry, inflation, monetary transmission, monetary policy, extensive margin

Firm Entry, Inflation and the Monetary Transmission Mechanism

This paper estimates a business cycle model with endogenous firm entry by matching impulse responses to a monetary policy shock in US data. Our VAR includes net business formation, profits and markups. We evaluate two channels through which entry may influence the monetary transmission process. Through the competition effect, the arrival of new entrants makes the demand for existing goods more elastic, and thus lowers desired markups and prices. Through the variety effect, increased firm and product entry raises consumption utility and thereby lowers the cost of living. This implies higher markups and, through the New Keynesian Phillips Curve, lower inflation. While the proposed model does a good job at matching the observed dynamics, it generates insufficient volatility of markups and profits. Estimates of standard parameters are largely unaffected by the introduction of firm entry. Our results lend support to the variety effect; however, we find no evidence for the competition effect.entry, inflation, monetary transmission, monetary policy, extensive margin

Employment, Hours and the Welfare Effects of Intra-Firm Bargaining

Ce Working Paper fait l'objet d'une publication in Journal of Monetary Economics, Elsevier 〈https://www.sciencedirect.com/science/article/abs/pii/S0304393218305294〉〈hal-01995026〉Intra-firm bargaining between a multiple-worker firm and an individual employee leads to overhiring. Taking advantage of the decreasing returns to scale in employment, the firm can reduce the marginal product by hiring an additional worker, thereby reducing the bargaining wage paid to all existing employees. We show that this externality is amplified when firms can adjust hours per worker as well as employment. Hours are too low at the steady state. This misallocation of labor leads to sizeable welfare losses. Our finding is important for economies in which hours adjustment play an important role as it does in many Euro Area countries

BLUE-based NO2 data assimilation at urban scale

International audienceWe aim at optimally combining air quality computations, from the Gaussian model ADMS Urban, and ground observations at urban scale. An ADMS simulation generated NO2 concentration fields across Clermont-Ferrand (France) down to street level, every 3 h for the full year 2008. A monitoring network composed of nine fixed stations provided hourly observations to be assimilated. Every 3 h, we compute the so-called BLUE (best linear unbiased estimator), which is a concentration field merging ADMS outputs and ground observations. Its error variance is supposed to be minimal under given assumptions regarding the errors on observations and model simulations. A key step lies in the modeling of error covariances between the computed NO2 concentrations across the city. We introduce a parameterized covariance which heavily relies on the road network. The covariance between two locations depends on the distance of each location to the road network and on the distance between the locations along the road network. Efficient parameters for the covariances are primarily chosen according to prior assumptions, χ2 diagnosis and leave-one-out cross-validations. According to the cross-validations, the improvements due to the assimilation seem moderately far from the observation network, but the root mean square error roughly decreases by 30-50% in the main city where the station density is high. The method is computationally tractable for the generation of improved concentration fields over a long period, or for day-to-day forecasts

Ventx factors function as Nanog-like guardians of developmental potential in Xenopus

International audienceVertebrate development requires progressive commitment of embryonic cells into specific lineages through a continuum of signals that play off differentiation versus multipotency. In mammals, Nanog is a key transcription factor that maintains cellular pluripotency by controlling competence to respond to differentiation cues. Nanog orthologs are known in most vertebrates examined to date, but absent from the Anuran amphibian Xenopus. Interestingly, in silico analyses and literature scanning reveal that basal vertebrate ventral homeobox (ventxs) and mammalian Nanog factors share extensive structural, evolutionary and functional properties. Here, we reassess the role of ventx activity in Xenopus laevis embryos and demonstrate that they play an unanticipated role as guardians of high developmental potential during early development. Joint over-expression of Xenopus ventx1.2 and ventx2.1-b (ventx1/2) counteracts lineage commitment towards both dorsal and ventral fates and prevents msx1-induced ventralization. Furthermore, ventx1/2 inactivation leads to down-regulation of the multipotency marker oct91 and to premature differentiation of blastula cells. Finally, supporting the key role of ventx1/2 in the control of developmental potential during development, mouse Nanog (mNanog) expression specifically rescues embryonic axis formation in ventx1/2 deficient embryos. We conclude that during Xenopus development ventx1/2 activity, reminiscent of that of Nanog in mammalian embryos, controls the switch of early embryonic cells from uncommitted to committed states

Systematic map of the literature on carbon lock-in induced by long-lived capital

Long-lived capital-stocks (LLCS) such as infrastructure and buildings have significant and long-lasting implications for greenhouse gas emissions. They contribute to carbon lock-in and may hinder a rapid decarbonization of energy systems. Here we provide a systematic map of the literature on carbon lock-in induced by LLCS. Based on a structured search of the Web of Science and Scopus, we identified 226 publications from 38 095 search results using a supervised machine learning approach. We show biases toward power generation and toward developed countries. We also identify 11 indicators used to quantify carbon lock-in. Quantifications of committed emissions (cumulative emissions that would occur over the remaining operational lifetime of an asset) or stranded assets (premature retirement/retrofitting or under-utilization of assets along a given pathway) are the most commonly used metrics, whereas institutional indicators are scarcely represented. The synthesis of quantifications shows that (i) global committed emissions have slightly increased over time, (ii) coal power plants are a major source of committed emissions and are exposed to risk of becoming stranded, (iii) delayed mitigation action increases stranded assets and (iv) sectoral distribution and amount of stranded assets differ between countries. A thematic analysis of policy implications highlights the need to assure stability and legitimacy of climate policies and to enable coordination between stakeholders. Carbon pricing is one of the most cited policy instrument, but the literature emphasizes that it should not be the only instrument used and should instead be complemented with other policy instruments, such as technical regulations and financial support for low carbon capital deployment. Further research is warranted on urban-scale, in developing countries and outside the electricity generation sector, notably on buildings, where stranded assets could be high.BMBF, 01LA1826A, Ökonomie des Klimawandels - Verbundprojekt: Die politische Ökonomie eines globalen Kohleausstiegs (PEGASOS) - Teilprojekt 1: Koordination, Analyse der politischen Ökonomie vergangener KohleausstiegeEC/H2020/821124/EU/Next generation of AdVanced InteGrated Assessment modelling to support climaTE policy making/NAVIGAT

A temporary social parasite of tropical plant-ants improves the fitness of a myrmecophyte

Myrmecophytes offer plant-ants a nesting place in exchange for protection from their enemies, particularly defoliators. These obligate ant-plant mutualisms are common model systems for studying factors that allow horizontally transmitted mutualisms to persist since parasites of ant-myrmecophyte mutualisms exploit the rewards provided by host plants whilst providing no protection in return. In pioneer formations in French Guiana, Azteca alfari and Azteca ovaticeps are known to be mutualists of myrmecophytic Cecropia (Cecropia ants). Here, we show that Azteca andreae, whose colonies build carton nests on myrmecophytic Cecropia, is not a parasite of Azteca-Cecropia mutualisms nor is it a temporary social parasite of A. alfari; it is, however, a temporary social parasite of A. ovaticeps. Contrarily to the two mutualistic Azteca species that are only occasional predators feeding mostly on hemipteran honeydew and food bodies provided by the host trees, A. andreae workers, which also attend hemipterans, do not exploit the food bodies. Rather, they employ an effective hunting technique where the leaf margins are fringed with ambushing workers, waiting for insects to alight. As a result, the host trees' fitness is not affected as A. andreae colonies protect their foliage better than do mutualistic Azteca species resulting in greater fruit production. Yet, contrarily to mutualistic Azteca, when host tree development does not keep pace with colony growth, A. andreae workers forage on surrounding plants; the colonies can even move to a non-Cecropia tree

Inherited biotic protection in a Neotropical pioneer plant

Chelonanthus alatus is a bat-pollinated, pioneer Gentianaceae that clusters in patches where still-standing, dried-out stems are interspersed among live individuals. Flowers bear circum-floral nectaries (CFNs) that are attractive to ants, and seed dispersal is both barochorous and anemochorous. Although, in this study, live individuals never sheltered ant colonies, dried-out hollow stems - that can remain standing for 2 years - did. Workers from species nesting in dried-out stems as well as from ground-nesting species exploited the CFNs of live C. alatus individuals in the same patches during the daytime, but were absent at night (when bat pollination occurs) on 60.5% of the plants. By visiting the CFNs, the ants indirectly protect the flowers - but not the plant foliage - from herbivorous insects. We show that this protection is provided mostly by species nesting in dried-out stems, predominantly Pseudomyrmex gracilis. That dried-out stems remain standing for years and are regularly replaced results in an opportunistic, but stable association where colonies are sheltered by one generation of dead C. alatus while the live individuals nearby, belonging to the next generation, provide them with nectar; in turn, the ants protect their flowers from herbivores. We suggest that the investment in wood by C. alatus individuals permitting stillstanding, dried-out stems to shelter ant colonies constitutes an extended phenotype because foraging workers protect the flowers of live individuals in the same patch. Also, through this process these dried-out stems indirectly favor the reproduction (and so the fitness) of the next generation including both their own offspring and that of their siblings, alladding up to a potential case of inclusive fitness in plants

Indicateurs de suivi de l'activité scientifique de l'Inria

La Commission d'Evaluation de l'Inria a mis en place début 2020, à la demande de la Direction Générale, un groupe de travail visant à réfléchir à des indicateurs pour l'analyse qualitative de l'activité scientifique de l'Institut. Ce document est le fruit des discussions de ce groupe, enrichies par les échanges avec la Direction Générale d'Inria et avec l'ensemble de la Commision d'Evaluation. Au-delà de cette « commande », il nous a semblé important de saisir cette opportunité pour mener une réflexion collective, qui dépasse le cadre de notre Institut, sur les indicateurs, et sur ce qu'ils peuvent ou ne peuvent pas dire de nos pratiques scientifiques