Bank loss provisioning rules: a convenient scapegoat in the Covid-19 crisis?

Better coordination between prudential regulators and accounting standard-setters will help banks withstand the crisis, writes Lucas Mahieu

Correcting agglomeration economies: How air pollution matters

The aim of the paper is to correct standard measures of agglomeration economies in order to account for air pollution generated by commuting. This paper examines the impact of nitrogen oxide (NOX) on worker productivity. NOX emissions are primarily released by the transportation sector. Literature on agglomeration economies is abundant and highlights the positive role of density on productivity. Nevertheless, this literature does not take into account the environmental impact generated by a better accessibility, namely commuting. We rst develop a general framework to estimate the agglomeration economies for the 304 French employment areas. In line with the literature, we nd an estimate of 0.05 for the elasticity coe cient of productivity with respect to density. Then, we introduce NOX emissions. The estimates suggest that emissions reduce the positive e ect of density on productivity by more 13%. The model con rms that air pollution matters. Agglomeration economies should be corrected by the environmental impacts associated with the enhancement of accessibility such as the implementation of a new transport infrastructure or policy

Scalable k-Means Clustering via Lightweight Coresets

Coresets are compact representations of data sets such that models trained on a coreset are provably competitive with models trained on the full data set. As such, they have been successfully used to scale up clustering models to massive data sets. While existing approaches generally only allow for multiplicative approximation errors, we propose a novel notion of lightweight coresets that allows for both multiplicative and additive errors. We provide a single algorithm to construct lightweight coresets for k-means clustering as well as soft and hard Bregman clustering. The algorithm is substantially faster than existing constructions, embarrassingly parallel, and the resulting coresets are smaller. We further show that the proposed approach naturally generalizes to statistical k-means clustering and that, compared to existing results, it can be used to compute smaller summaries for empirical risk minimization. In extensive experiments, we demonstrate that the proposed algorithm outperforms existing data summarization strategies in practice.Comment: To appear in the 24th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining (KDD

HTLV-3/STLV-3 and HTLV-4 Viruses: Discovery, Epidemiology, Serology and Molecular Aspects

Human T cell leukemia/lymphoma virus Type 1 and 2 (HTLV-1 and HTLV-2), together with their simian counterparts (STLV-1, STLV-2), belong to the Primate T lymphotropic viruses group (PTLV). The high percentage of homologies between HTLV-1 and STLV-1 strains, led to the demonstration that most HTLV-1 subtypes arose from interspecies transmission between monkeys and humans. STLV-3 viruses belong to the third PTLV type and are equally divergent from both HTLV-1 and HTLV-2. They are endemic in several monkey species that live in West, Central and East Africa. In 2005, we, and others reported the discovery of the human homolog (HTLV-3) of STLV-3 in two asymptomatic inhabitants from South Cameroon whose sera exhibited HTLV indeterminate serologies. More recently, two other cases of HTLV-3 infection in persons living in Cameroon were reported suggesting that this virus is not extremely rare in the human population living in Central Africa. Together with STLV-3, these human viral strains belong to the PTLV-3 group. A fourth HTLV type (HTLV-4) was also discovered in the same geographical area. The overall PTLV-3 and PTLV-4 genomic organization is similar to that of HTLV-1 and HTLV-2 with the exception of their long terminal repeats (LTRs) that contain only two 21 bp repeats. As in HTLV-1, HTLV-3 Tax contains a PDZ binding motif while HTLV-4 does not. An antisense transcript was also described in HTLV-3 transfected cells. PTLV-3 molecular clones are now available and will allow scientists to study the viral cycle, the tropism and the possible pathogenicity in vivo. Current studies are also aimed at determining the prevalence, distribution, and modes of transmission of these viruses, as well as their possible association with human diseases. Here we will review the characteristics of these new simian and human retroviruses, whose discovery has opened new avenues of research in the retrovirology field

The Impacts of public transport policies on a non mobility area: French study case in the north of France

Many regeneration projects aim at producing a benefit of the population around them. However, it may happen that the socio-economic problems and needs of the territory involved are not completely understood. This paper reports on a case study of the northern part of France, namely Bassin-Minier, which used to be a coal mining area. It is a partic ular metropolitan area with a specific geography and spatial distribution, which faces different social problems, along with a limited public transportation system. Focus groups were used as a methodology to disentangle the transport behaviour, situation and needs of the people living or working in this specific territory due to the limited availability of other recent sources of information. We have chosen to focus specifically on groups with limited availability of transportation or in risk of social exclusion. This research also aims at contrasting different future and recent transport and regeneration projects with the population under study, to understand whether these projects are found beneficial by them

Why would passive funds invest in corporate governance?

Ownership by passively managed funds has increased over the last 20 years. They are called passive because they hold stock in proportion to the company’s weight on a published index, such as the FTSE100 or the Dow Jones Industrial Average. Being tied to indexes means they cannot modify the weight of a specific company in their portfolio. Henry Friedman and Lucas Mahieux explore passive funds’ incentives to monitor the firms they invest in and present a nuanced view of the role that these funds play in firms’ corporate governance

HTLV-1 and Innate Immunity

Innate immunity plays a critical role in the host response to a viral infection. The innate response has two main functions. First, it triggers effector mechanisms that restrict the infection. Second, it primes development of the adaptive response, which completes the elimination of the pathogen or of infected cells. In vivo, HTLV-1 infects T lymphocytes that participate in adaptive immunity but also monocytes and dendritic cells that are major players in innate immunity. Herein, we will review the interplay between HTLV-1 and innate immunity. Particular emphasis is put on HTLV-1-induced alteration of type-I interferon (IFN-I) function. In vitro, the viral Tax protein plays a significant role in the alteration of IFN synthesis and signaling. Despite this, IFN-I/AZT treatment of Adult T-cell Leukemia/Lymphoma (ATLL) patients leads to complete remission. We will discuss a model in which exogenous IFN-I could act both on the microenvironment of the T-cells to protect them from infection, and also on infected cells when combined with other drugs that lead to Tax down-regulation/degradation

Mining Large-Scale Music Data Sets

Large collections of music audio are now common and present an interesting research opportunity: what statistical patterns and structure can be discovered across thousands or millions of examples? Unfortunately, copyright restrictions can interfere with access to such collections, so we have developed the Million Song Dataset, including derived features but not the original audio, to support commercial-scale music analysis on a common, research database. The audio features are augmented by a wide range of metadata including lyrics, tags, and listener playcounts. Now the database is ready, we have begun analyzing the content, including tasks such as identifying cover songs -- significantly harder for such a large collection