Comparison of meta-learners for estimating multi-valued treatment heterogeneous effects

Conditional Average Treatment Effects (CATE) estimation is one of the main challenges in causal inference with observational data. In addition to Machine Learning based-models, nonparametric estimators called meta-learners have been developed to estimate the CATE with the main advantage of not restraining the estimation to a specific supervised learning method. This task becomes, however, more complicated when the treatment is not binary as some limitations of the naive extensions emerge. This paper looks into meta-learners for estimating the heterogeneous effects of multi-valued treatments. We consider different meta-learners, and we carry out a theoretical analysis of their error upper bounds as functions of important parameters such as the number of treatment levels, showing that the naive extensions do not always provide satisfactory results. We introduce and discuss meta-learners that perform well as the number of treatments increases. We empirically confirm the strengths and weaknesses of those methods with synthetic and semi-synthetic datasets.Comment: 42 pages, 9 figures, to appear in ICML 2023 conferenc

O JORNALISMO DIGITAL NAS REDES SOCIAIS: CARACTERÍSTICAS E NOVAS ESTRATÉGIAS PARA A IMPRENSA ATUAL

In the era of digital communication, social networks have significantly transformed the way news is produced, disseminated and consumed, and have become an essential tool for the work of journalists. Today, platforms such as Facebook, Instagram and Twitter offer the possibility of interacting directly with the public, obtaining immediate feedback and creating content in new formats and disseminating it virally. The objective of this article is to explore different strategies that journalistic media use in their social networks to generate information and connect with readers. For this purpose, a methodology based on a descriptive method and on the analysis of informative content is used. It is concluded that the strategies used seek speed in the publication of news, constant interaction with the audience and the production of attractive multimedia content to improve the news experience of readers.  En la era de la comunicación digital, las redes sociales han transformado significativamente la forma de producir, distribuir y consumir contenidos informativos convirtiéndose en una herramienta imprenscindible para el ejercicio de la práctica periodística. En la actualidad, plataformas como Facebbok, Instagram y Twitter ofrecen un espacio donde los periodistas pueden interactuar directamente con su audiencia, obtener retroalimentación instantánea, producir contenidos en formatos atractivos e innovadores y difundir noticias de una manera viral. Este artículo pretende explorar algunas estrategias de innovación periodística asociadas al uso de las redes sociales para la generación de contenidos informativos y la interacción con las audiencias. Para ello, se utiliza una metodología basada en un enfoque descriptivo y en el análisis de contenido informativo. Se concluye que las estrategias utilizadas por los periodistas en las redes sociales buscan la inmediatez en la difusión de las noticias, la interacción constante con su audiencia y la elaboración de contenidos multimedia atractivos para enriquecer la experiencia informativa de sus lectores.Na era da comunicação digital, as redes sociais transformaram significativamente a maneira de produzir, distribuir e consumir conteúdo informativo, tornando-se uma ferramenta indispensável para a prática jornalística. Atualmente, plataformas como o Facebook, Instagram e Twitter oferecem um espaço onde os jornalistas podem interagir diretamente com seu público, obter feedback instantâneo, produzir conteúdo em formatos atraentes e inovadores e disseminar notícias de maneira viral. Este artigo pretende explorar algumas estratégias de inovação jornalística associadas ao uso das redes sociais para a geração de conteúdo informativo e interação com as audiências. Para isso, é utilizada uma metodologia baseada em uma abordagem descritiva e na análise de conteúdo informativo. Conclui-se que as estratégias utilizadas pelos jornalistas nas redes sociais buscam a imediatidade na divulgação das notícias, a interação constante com seu público e a criação de conteúdo multimídia atraente para enriquecer a experiência informativa de seus leitores

Hydrological modeling of spatial and temporal variations in streamflow due to multiple climate change scenarios in northwestern Morocco

Climate change is one of the most important factors impacting hydrological regimes. In this paper, climate change impact on streamflow of Loukkos basin (northwestern Morocco) is evaluated using SWAT model for three future periods: near (2021–2040), mid (2041–2070), and far (2071–2100), compared to baseline 1981–2020. A set of bias-corrected climate models was used: five regional climate models (EURO-CORDEX), four global climate models (CMIP6) and their ensemble mean, under two representative concentration pathways respectively (RCP 4.5; RCP 8.5) and (SSP2-4.5; SSP5-8.5). Furthermore, SUFI-2 algorithm in SWAT-CUP was performed to calibrate (1981–1997), validate (1998–2015), and analyze uncertainty for each dataset at ten hydrological stations. In most stations, statistical performance indicated a good simulation, with a Nash–Sutcliffe efficiency (NSE) greater than 0.77 and percent bias (PBIAS) within ±10% on a monthly basis. Overall, 82% of models indicated that future climate could decline streamflow. The largest decrease would be for 2071–2100 and under RCP 8.5/SSP5-8.5. Our findings could help planners and policymakers in developing reasonable water management policies and climate change adaptation measures

Mesenteric schwannoma: about a rare disease

Parmi les tumeurs du mésentère, le schwannome est une variété exceptionnelle. Il fait partie des tumeurs conjonctives. Elles se caractérisent habituellement par leur latence clinique et leur faible potentiel de malignité. Nous rapportons un cas de schwannome mésentérique d’allure macroscopique maligne mais histologiquement bénin. Ce paradoxe clinique ainsi que la rareté de la tumeur font l’originalité de notre observation. La nature de la tumeur est donnée par histologie. La différenciation entre le caractère bénin et malin reste toujours difficile et parfois, seule, l’évolution peut trancher. Mots-clés Schwannome du mésentère, Tumeurs conjonctives, Macroscopie maligne mais histologie bénigne Le traitement repose sur l’exérèse chirurgicale. Le pronostic des schwannomes du mésentère est difficile à apprécier en raison du caractère exceptionnel ou de la rareté des cas rapportés. Les facteurs de mauvais pronostic sont : l’âge extrême, les schwannomes dans le cadre de la maladie de Von Recklinghausen (VR), la grande taille tumorale, le degré de la différenciation, l’importance de l’activité nécrotique et de l’activité mitotique