Improving sample efficiency and multi-agent communication in RL-based train rescheduling

We present preliminary results from our sixth placed entry to the Flatland international competition for train rescheduling, including two improvements for optimized reinforcement learning (RL) training efficiency, and two hypotheses with respect to the prospect of deep RL for complex real-world control tasks: first, that current state of the art policy gradient methods seem inappropriate in the domain of high-consequence environments; second, that learning explicit communication actions (an emerging machine-to-machine language, so to speak) might offer a remedy. These hypotheses need to be confirmed by future work. If confirmed, they hold promises with respect to optimizing highly efficient logistics ecosystems like the Swiss Federal Railways railway network

Entwicklung eines Methodologie-Tools für CO2-Zertifikate im Rahmen einer bench-markbasierten N-Reduktion in der Schweizer Landwirtschaft

Im folgenden Bericht wird eine erste Analyse verschiedener Bausteine sowie eine gesamthafte Beurteilung des Potenzials einer benchmarkbasierten Methodologie unternommen, um bodenbürtige Lachgasemissionen aus der Landwirtschaft zu reduzieren und daraus CO2-Zertifikate für die Kompensation unter den Aktivitäten der Stiftung KliK zu generieren. Der Fokus in diesem Bericht liegt auf einem neuen Berechnungstool für bodenbürtige Lachgasemissionen auf der Ebene von Landwirtschaftsbetrieben als grundlegender Baustein für entsprechende Offset-Methodologien. Dies ist der Abschlussbericht einer Vorstudie zu dieser Thematik, der bei positiver Beurteilung des Potenzials dieses Zugangs eine vertiefte Hauptstudie und Umsetzungsphase für eine solche Methodologieentwicklung gefolgt wäre. Da das Potenzial in Relation zum Aufwand aber als gering beurteilt wird und institutionelle Unsicherheiten bei der Validierung und Zulassung eines solchen Ansatzes gross sind, und entsprechende Zeitverzögerungen erwartet werden, wird da-von abgesehen, diesen im Rahmen der Aktivitäten der Stiftung Klik bis 2020 weiter zu verfolgen. Die Notwendigkeit und Wichtigkeit des hier im Folgenden vorgeschlagenen und diskutierten Berechnungstools wird aber von allen Seiten anerkannt und es würde begrüsst werden, wenn dieses dennoch weiterentwickelt werden könnte (idealerweise in enger Zusammenarbeit mit BLW und BAFU) und längerfristig auch bei Emissionsreduktionsberechnungen zum Einsatz gelangen würde

Mitigation of atmospheric perturbations and solid Earth movements in a TerraSAR-X time-series

The TerraSAR-X (TSX) synthetic aperture radar (SAR) marks the recent emergence of a new generation of spaceborne radar sensors that can for the first time lay claim to localization accuracies in the sub-meter range. The TSX platform's extremely high orbital stability and the sensor's hardware timing accuracy combine to enable direct measurements of atmospheric refraction and solid Earth movements. By modeling these effects for individual TSX acquisitions, absolute pixel geolocation accuracy on the order of several centimeters can be achieved without need for even a single tiepoint. A 16-month time series of images was obtained over a fixed test site, making it possible to validate both an atmospheric refraction and a solid Earth tide model, while at the same time establishing the instrument's long-term stability. These related goals were achieved by placing trihedral corner reflectors (CRs) at the test site and estimating their phase centers with centimeter-level accuracy using differential GPS (DGPS). Oriented in pairs toward a given satellite track, the CRs could be seen as bright "points” in the images, providing a geometric reference set. SAR images from the high-resolution spotlight (HS) mode were obtained in alternating ascending and descending orbit configurations. The highest-resolution products were selected for their small sample dimensions, as positions can be more precisely determined. Based on the delivered product annotations, the CR image positions were predicted, and these predictions were compared with their measured image positions both before and after compensation for atmospheric refraction and systematic solid Earth deviations. It was possible to show that when the atmospheric distortion and Earth tides are taken into account, the TSX HS products have geolocation accuracies far exceeding the specified requirements. Furthermore, this accuracy was maintained for the duration of the 16-month test period. It could be demonstrated that with a correctly calibrated sensor, and after accounting for atmospheric and tidal effects, tiepoint-free geolocation is possible with TSX with an absolute product accuracy of about 5c

Organic Farming, Climate Change Mitigation and Beyond. Reducing the environmental impacts of eu agriculture

Sustainably feeding the growing world population and preventing dangerous climate change are two of the major challenges facing society today. While there is a growing understanding of the complexity of the links between these challenges and of the global degradation of the environment, the contribution of food and farming to climate change mitigation is all too often looked at from the single perspective of greenhouse gas (GHG) emissions per hectare or kilogram of product. This narrow view fails to account for the vast array of ways that food and farming contribute to climate change, as well as the destructive effects of industrial agriculture on soils, biodiversity and the natural resources on which we depend for food production. The impact of agriculture practices, food wastage, and diets must all be evaluated if we are to understand how food and farming can positively contribute to climate change mitigation and adaptation, while simultaneously providing food security. The issue about what is produced to meet human needs, what is produced for intermediate production purposes (e.g. livestock feed) and what is wasted between the field and the kitchen, needs to be part of the discussion. To provide healthy food in a sustainable way, we need to transform the food & farming system and transition to agriculture and food production that can adapt to unavoidable climate change, preserve our natural heritage such as biodiversity, sustains the quality of our soils, and improve the livelihood of farmers. This report aims to provide a comprehensive discussion of these varied, yet interlinked, issues

Social Comparison on Social Media and Mental Health: A Scoping Review

Soziale Medien bieten ihren Nutzer*innen eine Vielzahl von Möglichkeiten zur Online-Selbstdarstellung und stellen somit ein optimales Umfeld für soziale Vergleiche dar. Mit zunehmender Beliebtheit sozialer Medien wächst in der Öffentlichkeit und in der Wissenschaft die Sorge über negative Auswirkungen sozialer Online-Vergleiche auf die psychische Gesundheit der Nutzer*innen. Die wissenschaftliche Forschung zu diesem Thema nimmt rapide zu, wodurch das Feld heterogener und schwieriger zu überblicken wird. Ziel dieses Scoping Reviews ist es daher, eine systematische Übersicht über das fragmentierte Forschungsfeld zu sozialen Vergleichen in sozialen Medien und psychischer Gesundheit zu bieten. Anhand vordefinierter Einschlusskriterien wurden 131 quantitative Studien systematisch identifiziert, um das Forschungsfeld zu kartieren. Die Ergebnisse zeigen, dass die Zahl der Studien seit 2011 zugenommen hat und dass Erstautoren aus den Vereinigten Staaten und aus dem Fachbereich Psychologie die meisten Beiträge lieferten. In Bezug auf die untersuchten Vergleichsrichtungen, Vergleichsdimensionen und Indikatoren für psychische Gesundheit zeigen die Analysen, dass sich die Studien vor allem auf Aufwärtsvergleiche hinsichtlich verschiedener Vergleichsdimensionen sowie hedonisches Wohlbefinden konzentrierten, während Abwärtsvergleiche und andere Facetten der psychischen Gesundheit im Feld derzeit unterrepräsentiert sind.Social media offer their users a variety of opportunities for online self-presentation and thus represent an optimal environment for social comparisons. With the increasing popularity of social media, there is growing concern in public and scientific discourse about negative effects of online social comparisons on users' mental health. Research output on this topic is increasing rapidly, making the field more heterogeneous and difficult to oversee. This scoping review therefore aims to provide a systematic mapping of the fragmented research field on social media comparisons and mental health. Using predefined inclusion criteria, 131 quantitative studies were systematically identified to map the research field. The results showed that the number of studies has grown since 2011 and that first authors from the United States and Psychology departments were the main contributors. With regard to the comparison directions, comparison dimensions, and indicators of mental health examined, the analyses demonstrate that the studies primarily focused on upward comparisons on diverse dimensions and hedonic well-being, whereas downward comparisons and other facets of mental health are currently under-represented in the field

Studying problems, not problematic usage: Do mobile checking habits increase procrastination and decrease well-being?

Most prior research on the effects of mobile and social media on well-being has worked from either the “technology addiction” or “screen time” approach. Yet these frameworks struggle with considerable conceptual and methodological limitations. The present study discusses and tests an established but understudied alternative, the technology habit approach. Instead of conflating mobile usage with problems (i.e., addictive/problematic usage) or ignoring users’ psychological engagement with mobiles (i.e., screen time), this approach investigates how person-level (habit strength) and day-level aspects of mobile habits (perceived interruptions and the urge to check) contribute to a key problem outcome, procrastination, as well as affective well-being and meaningfulness. In a five-day diary study with N = 532 student smartphone users providing N = 2,331 diary entries, mobile checking habit strength, perceived interruptions, and the urge to check together explained small to moderate amounts of procrastination. Procrastination, in turn, was linked to lower affective well-being and meaningfulness. Yet mobile habits showed only very small or no direct associations with affective well-being and meaningfulness. By separating habitual mobile connectivity from problem outcomes and well-being measures, this research demonstrates a promising alternative to the study of digital well-being

New Constructions of Obviously Strategyproof Mechanisms

Catering to the incentives of people with limited rationality is a challenging research direction that requires novel paradigms to design mechanisms. Obviously strategy-proof (OSP) mechanisms have recently emerged as the concept of interest to this research agenda. However, the majority of the literature in the area has either highlighted the shortcomings of OSP or focused on the “right” definition rather than on the construction of these mechanisms. Here, we give the first set of tight results on the approximation guarantee of OSP mechanisms for scheduling related machines and a characterization of set system instances for which OSP mechanisms that return optimal solutions exist. By extending the well-known cycle monotonicity technique, we are able to concentrate on the algorithmic component of OSP mechanisms and provide some novel paradigms for their design, when private types belong to a set with few values. In essence, we prove that OSP encompasses careful interleaving of ascending and descending auctions

Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin