Lernbarrieren beim Fachwortlernen – zum Beispiel Mathematik

Im Unterricht mit sprachentwicklungsgestörten Lernenden ist es außerordentlich wichtig, dass beim Erwerb, bei der Speicherung und Automatisierung neuer Fachwörter Hilfestellungen im Unterricht installiert werden. Der Beitrag [zeigt auf], welche Methoden innerhalb der verschiedenen Phasen des Lernprozesses unterstützend wirksam sein können. (DIPF/Orig.

Repository of NSF Funded Publications and Data Sets: "Back of Envelope" 15 year Cost Estimate

In this back of envelope study we calculate the 15 year fixed and variable costs of setting up and running a data repository (or database) to store and serve the publications and datasets derived from research funded by the National Science Foundation (NSF). Costs are computed on a yearly basis using a fixed estimate of the number of papers that are published each year that list NSF as their funding agency. We assume each paper has one dataset and estimate the size of that dataset based on experience. By our estimates, the number of papers generated each year is 64,340. The average dataset size over all seven directorates of NSF is 32 gigabytes (GB). A total amount of data added to the repository is two petabytes (PB) per year, or 30 PB over 15 years. The architecture of the data/paper repository is based on a hierarchical storage model that uses a combination of fast disk for rapid access and tape for high reliability and cost efficient long-term storage. Data are ingested through workflows that are used in university institutional repositories, which add metadata and ensure data integrity. Average fixed costs is approximately $.0.90/GB over 15-year span. Variable costs are estimated at a sliding scale of$150 - $100 per new dataset for up-front curation, or$4.87 – $3.22 per GB. Variable costs reflect a 3 The total projected cost of the data and paper repository is estimated at$167,000,000 over 15 years of operation, curating close to one million of datasets and one million papers. After 15 years and 30 PB of data accumulated and curated, we estimate the cost per gigabyte at $5.56. This$167 million cost is a direct cost in that it does not include federally allowable indirect costs return (ICR). After 15 years, it is reasonable to assume that some datasets will be compressed and rarely accessed. Others may be deemed no longer valuable, e.g., because they are replaced by more accurate results. Therefore, at some point the data growth in the repository will need to be adjusted by use of strategic preservation

Fractal analysis of resting state functional connectivity of the brain

A variety of resting state neuroimaging data tend to exhibit fractal behavior where its power spectrum follows power-law scaling. Resting state functional connectivity is significantly influenced by fractal behavior which may not directly originate from neuronal population activities of the brain. To describe the fractal behavior, we adopted the fractionally integrated process (FIP) model instead of the fractional Gaussian noise (FGN) since the FIP model covers more general aspects of fractality than the FGN model. We also introduce a novel concept called the nonfractal connectivity which is defined as the correlation of short memory independent of fractal behavior, and compared it with the fractal connectivity which is an asymptotic wavelet correlation. We propose several wavelet-based estimators of fractal connectivity and nonfractal connectivity for a multivariate fractionally integrated noise (mFIN). The performance of these estimators was evaluated through simulation studies and the analyses of resting state functional MRI data of the rat brain.Comment: The 2012 International Joint Conference on Neural Network

Offset balancing in pseudo-correlation radiometers for CMB measurements

Radiometeric CMB measurements need to be highly stable and this stability is best obtained with differential receivers. The residual 1/f noise in the differential output is strongly dependent on the radiometer input offset which can be cancelled using various balancing strategies. In this paper we discuss a software method implemented in the Planck-LFI pseudo-correlation receivers which uses a tunable "gain modulation factor, r, in the sky-load difference. Numerical simulations and experimental data show how proper tuning of the parameter r ensures a very stable differential output with knee frequencies of the order of few mHz. Various approaches to calculate r using the radiometer total power data are discussed with some examples relevant to Planck-LFI. Although the paper focuses on pseudo-correlation receivers and the examples are relative to Planck-LFI, the proposed method and its analysis is general and can be applied to a large class of differential radiometric receivers.Comment: 12 pages, 8 figures, accepted for publication in A&A (updated version with few editorial changes

A new estimate of afrotherian phylogeny based on simultaneous analysis of genomic, morphological, and fossil evidence

<p>Abstract</p> <p>Background</p> <p>The placental mammalian clade Afrotheria is now supported by diverse forms of genomic data, but interordinal relationships within, and morphological support for, the group remains elusive. As a means for addressing these outstanding problems, competing hypotheses of afrotherian interordinal relationships were tested through simultaneous parsimony analysis of a large data set (> 4,590 parsimony informative characters) containing genomic data (> 17 kb of nucleotide data, chromosomal associations, and retroposons) and 400 morphological characters scored across 16 extant and 35 extinct afrotherians.</p> <p>Results</p> <p>Parsimony analysis of extant taxa alone recovered the interordinal topology (Afrosoricida, ((Macroscelidea, Tubulidentata), (Hyracoidea, (Proboscidea, Sirenia)))). Analysis following addition of extinct taxa instead supported Afroinsectivora (Afrosoricida + Macroscelidea) and Pseudoungulata (Tubulidentata + Paenungulata), as well as Tethytheria (Proboscidea + Sirenia). This latter topology is, however, sensitive to taxon deletion and different placements of the placental root, and numerous alternative interordinal arrangements within Afrotheria could not be statistically rejected. Relationships among extinct stem members of each afrotherian clade were more stable, but one alleged stem macroscelidean (<it>Herodotius</it>) never grouped with that clade and instead consistently joined pseudoungulates or paenungulates. When character transformations were optimized onto a less resolved afrotherian tree that reflects uncertainty about the group's interordinal phylogeny, a total of 21 morphological features were identified as possible synapomorphies of crown Afrotheria, 9 of which optimized unambiguously across all character treatments and optimization methods.</p> <p>Conclusion</p> <p>Instability in afrotherian interordinal phylogeny presumably reflects rapid divergences during two pulses of cladogenesis – the first in the Late Cretaceous, at and just after the origin of crown Afrotheria, and the second in the early Cenozoic, with the origin of crown Paenungulata. Morphological evidence for divergences during these two pulses either never existed or has largely been "erased" by subsequent evolution along long ordinal branches. There may, nevertheless, be more morphological character support for crown Afrotheria than is currently assumed; the features identified here as possible afrotherian synapomorphies can be further scrutinized through future phylogenetic analyses with broader taxon sampling, as well as recovery of primitive fossil afrotherians from the Afro-Arabian landmass, where the group is likely to have first diversified.</p

Jetstream: A national science & engineering cloud. Globus World Lightning Talk.

Presentation highlighting the capabilities and purpose for the upcoming Jetstream system.Jetstream and related material to its operation are funded by the National Science Foundation under grant No. ACI-1445604

Three essays in empirical economics

In the preface of one of the most established textbooks "Economics" by Samuelson and Nordhaus (1998), the authors state that the ultimate goal of economics is to improve the living conditions of people in their everyday life". In this spirit, the underlying thesis empirically assesses three heterogenous topics which all can be linked via their impact on (economic) well-being. It contributes to the scientific landscape by tackling the questions at hand utilising novel and newly constructed data sets which have not been commonly used in economic research. The thesis comprises three chapters which will be summarised in the following. Gun Violence in the US: Correlates and Causes This chapter provides a county-level investigation of the economically-motivated gun violence in the US. To guide our empirical analysis, we develop a simple theoretical model which suggests that firearm-related robberies in a given county increase with the number of illegal guns and decrease with social capital and police intensity. Using detailed FBI data from 1986-2014, we find empirical evidence for the role of illegal guns, social capital, and police intensity in line with our theoretical predictions. To investigate the causal effect of illegal guns, we exploit plausibly exogenous variation in illegal firearm supplies due to gun thefts in contiguous states. The Size of the Middle Class and Educational Outcomes: Theory and Evidence from the Indian Subcontinent This chapter proposes a stylised model to derive the effect of a sizeable middle class on average educational outcomes. Under the reasonable assumptions, the model predicts that the spending share on education increases if the middle class becomes larger such that the size of the middle class has a positive impact on education. We test the relationship empirically by using village/neighbourhood level data from Indian household surveys. To tackle the the issue of potential endogeneity of the middle class share of the population, we propose a novel instrument that relies on the fraction of the population belonging to the third (middle) caste ("sudra"). Using this IV strategy, our empirical results support a positive effect. Go East: On the Impact of the Transsiberian Railway on Economic Development in Eastern Russia This chapter addresses the question whether or not large-scale infrastructure investments have a causal effect of local economic development. By using a novel instrumental variable approach based on historical trade and travel routes across the Russian East, I am able to identify a causal and negative effect of remoteness to the Transsiberian Railway on local economic activity as measured by nocturnal lights emission.Im Vorwort eines der am meisten verwendeten Lehrbücher "Economics" von Samuelson und Nordhaus (1998) postulieren die Autoren, dass das ultimative Ziel eines jeden Ökonomen sein sollte, die alltäglichen Lebensumstände jedes Menschen zu verbessern. In diesem Sinne untersucht die vorliegende Arbeit drei heterogene Fragestellungen empirisch. Diese sind alle durch ihren Einfluss auf (wirtschaftliche) Wohlfahrt verbunden. Die Arbeit trägt zur wissenschaftlichen Landschaft bei indem sie die zugrundeliegenden Fragen unter Zuhilfenahme neuer und neu konstruierter Datensätze adressiert, welche bisher kaum bis garnicht verwendet wurden. Die Arbeit umfasst drei Projekte, welche im Folgenden zusammengefasst werden. Gun Violence in the US: Correlates and Causes Dieses Kapitel beinhaltet eine Untersuchung ökonomisch motivierter Waffengewalt auf dem County-Level. Um die empirische Analyse zu strukturieren wird ein einfaches theoretisches Modell vorgestellt. Dieses Modell impliziert, dass Raubüberfälle unter Zuhilfenahme von Schusswaffen in einem gegebenen County steigend in der Anzahl illegaler Schusswaffen und fallend im Niveau des Sozialkapitals sowie der Polizeipräsenz ist. Durch die Verwendung detaillierter FBI-Daten aus den Jahren 1986-2014 wird empirische Evidenz für die Rolle illegaler Feuerwaffen, Sozialkapital und Polizeipräsenz gefunden. Diese bestätigt die theoretischen Hypothesen. Um den kausalen Effekt illegaler Waffen zu identifizieren, wird die exogene Variation des illegalen Schusswaffenangebots in benachbarten Staaten genutzt. Diese wird anhand der als gestohlen gemeldeten Schusswaffen gemessen. The Size of the Middle Class and Educational Outcomes: Theory and Evidence from the Indian Subcontinent In diesem Kapitel wird ein stilisiertes theoretisches Modell vorgestellt um den durchschnittlichen Einfluss einer relativ großen Mittelschicht auf das durchschnittliche Bildungsniveau abzuleiten. Unter den getroffenen Annahmen prognostiziert das Modell dass der Anteil der Ausgaben für Bildung mit der relativen Größe der Mittelschicht ansteigt. Somit besteht ein positiver Zusammenhang zwischen der relativen Größe der Mittelschicht und dem durchschnittlichen Bildungsniveau. Dieser Zusammenhang wird dann empirisch überprüft. Als Datengrundlage dienen Dorf-/Nachbarschafts-Level Daten aus dem Indian Household Survey. Um dem Problem potentiell vorhandener Endogenität des Mittelschicht-Anteils zu begegnen, wird ein neuartiger IV-Ansatz vorgeschlagen. Dieser basiert auf dem Anteil der Bevölkerung, der zur dritten (mittleren) Kaste gehört. So können wir einen positiven, kausalen Effekt der relativen Größe der Mittelschicht auf das durchschnittliche Bildungsniveau nachweisen. Go East: On the Impact of the Transsiberian Railway on Economic Development in Eastern Russia Dieses Kapitel adressiert die Frage ob grossangelegte Infrastrukturprojekte einen kausalen Effekt auf das lokale Wirtschaftswachstum haben. Unter Zuhilfenahme eines neuartigen IV-Ansatzes, der auf historischen Handels- und Reiserouten durch den Osten Russlands basiert wird gezeigt, dass ein kausaler und negativer Effekt der Entfernung zur Transsibirischen Eisenbahn existiert. Ökonomische Entwicklung wird mangels vorhandener Daten mittels Nachtlicht-Emissionen approximiert

Correlation-based Data Representation

The Dagstuhl Seminar \u27Similarity-based Clustering and its Application to Medicine and Biology\u27 (07131) held in March 25--30, 2007, provided an excellent atmosphere for in-depth discussions about the research frontier of computational methods for relevant applications of biomedical clustering and beyond. We address some highlighted issues about correlation-based data analysis in this seminar postribution. First, some prominent correlation measures are briefly revisited. Then, a focus is put on Pearson correlation, because of its widespread use in biomedical sciences and because of its analytic accessibility. A connection to Euclidean distance of z-score transformed data outlined. Cost function optimization of correlation-based data representation is discussed for which, finally, applications to visualization and clustering of gene expression data are given