The Niceness of Unique Sink Orientations

Random Edge is the most natural randomized pivot rule for the simplex algorithm. Considerable progress has been made recently towards fully understanding its behavior. Back in 2001, Welzl introduced the concepts of \emph{reachmaps} and \emph{niceness} of Unique Sink Orientations (USO), in an effort to better understand the behavior of Random Edge. In this paper, we initiate the systematic study of these concepts. We settle the questions that were asked by Welzl about the niceness of (acyclic) USO. Niceness implies natural upper bounds for Random Edge and we provide evidence that these are tight or almost tight in many interesting cases. Moreover, we show that Random Edge is polynomial on at least $n^{\Omega(2^n)}$ many (possibly cyclic) USO. As a bonus, we describe a derandomization of Random Edge which achieves the same asymptotic upper bounds with respect to niceness and discuss some algorithmic properties of the reachmap.Comment: An extended abstract appears in the proceedings of Approx/Random 201

Kritische Bemerkungen zu Gedichten des Ausonius

Eine Anzahl textkritisch schwieriger Partien aus den Kleindichtungen des Ausonius, insbesondere der Bissula, den Epigrammen und den Parentalia, wird in Auseinandersetzung mit der modernen Forschungsliteratur neubesprochen. Dabei wird besonderes Gewicht gelegt auf die textkritischen Folgerungen, die sich aus den von Ausonius imitierten Vorbildern und gelegentlich auch aus späteren Imitationen seiner Gedichte ziehen lassen.In the present paper several difficult textual problems in the poems of Ausonius, especially in the Bissula, the epigrams and the Parentalia, are discussed with reference to modern commentaries. Emphasis is placed on what may be inferred for the textual criticism of Ausonius on the basis of the models that he imitated or, occasionally, on the basis of later imitations of his poems

Textkritische Uberlegungen zu hellenistischen Epigrammen

In dem Aufsatz werden einige schwierige Partien aus den hellenistischen Epigrammatikern Asklepiades, Leonidas, Hedylos, Kallimachos und Antipater besprochen. Die Überlegungen gehen aus von der kommentierten Ausgabe von Gow und Page

Discretization scheme for drift-diffusion equations with a generalized Einstein relation

Inspired by organic semiconductor models based on hopping transport introducing Gauss-Fermi integrals a nonlinear generalization of the classical Scharfetter-Gummel scheme is derived for the distribution function F(η)=1/(exp(-η)+γ). This function provides an approximation of the Fermi-Dirac integrals of different order and restricted argument ranges. The scheme requires the solution of a nonlinear equation per edge and continuity equation to calculate the edge currents. In the current formula the density-dependent diffusion enhancement factor, resulting from the generalized Einstein relation, shows up as a weighting factor. Additionally the current modifies the argument of the Bernoulli functions

Quantification of Iodine Supply: Representative Data on Intake and Urinary Excretion of Iodine from the German Population in 1996

Background/Methods: In Germany, iodine deficiency is common. In a representative group of 2,500 Germans (age >13 years), using a specially designed food questionnaire, the iodine intake was calculated. In addition, iodine and creatinine concentrations in spot urine samples were determined in three groups with a possibly increased risk of iodine deficiency (769 conscripts, 886 pairs of mothers and newborns) or future hyperthyroidism (574 adults, age range 50-70 years) from 26 representative regions. In four groups of controls (young and older male and female adults; n = 91), 24-hour urine iodine and creatinine were measured in six diurnal fractions to calculate group- and period-specific factors for the estimation of the 24-hour iodine excretion from data of iodine/creatinine ratio and time of micturition in spot urine samples. Results: The mean calculated iodine intake (excretion) was 119 mug/day for the group of Germans above 13 years; it was 119 mug/day (125 mug/day) for adults aged 50-70 years, 137 mug/day (125 mug/day)for conscripts, and 162 mug/day for breast-feeding mothers. The median iodine concentration (iodine/creatinine ratio) was 9.4 mug/dl (83 mug/g) in 566 adults aged 50-70 years, 8.3 mug/dl (57 mug/g) in 772 conscripts. and 5.6 mug/dl (156 mug/g) in 739 breast-fed newborns. Conclusions: Compared to older data, the iodine intake in Germany has increased. In 1996, the meticulously quantified average deficit was about 30% of the recommended iodine intake. Copyright (C) 2002 S. Karger AG, Basel

Wiederansiedlung seltener und gefährdeter Ackerwildpflanzen auf Ökobetrieben. Teilprojekt Witzenhausen: Versuche auf Praxisbetrieben

Abundance and diversity of arable weeds have been strongly declining in many European regions. Arable weeds are highly dependent on the respective type of management, and thus future programs for conservation of rare arable weeds have to establish a close and innovative integration with sustainable farming practice. The project “Restoration of local populations of rare and endangered arable field plants on organic farms in Germany” aims at developing applied scientific knowledge on new methods for conservation of arable weeds within farming systems. Two complementary research teams in contrasting regions in Germany test different approaches to reestablish arable weeds under various management systems and with different preconditions. The research team of the University of Kassel investigates the transfer of remnant populations of the species from nearby populations to organic fields. Two methods are being tested: the transplantation via seeds and the transplantation via transfer of surface soil

Evaluation of Manual vs. Speech Input When Using a Driver Information System in Real Traffic

The executed study evaluated the influence of manual and speech input on driving quality, stress and strain situation and user acceptance when using a Driver Information System (DIS). The study is part of the EU-project SENECA. 16 subjects took part in the investigations. A car was equipped with a modified DIS to carry out the evaluation in real traffic situations. The used DIS is a standard product with manual input control elements. This DIS was extended by a speech input system with a speaker independent speech recogniser. For the use of the different DIS devices (radio, CD player, telephone, navigation) 12 different representative tasks were given to the subjects. Independently the type of task speech input needs longer operation times than manual input. In case of complex tasks a distinct improvement of the driving quality can be observed with speech instead of manual input. The subjective safety feeling is stronger with speech than with manual input. With speech input the number of glances at the mirrors and aside is clearly higher than with manual input. The most frequent user errors can be explained by problems when spelling and by the selection of wrong speech commands. The rate of speech recognition errors amounts on the average to 20.6 % what makes it necessary to increase the recognition performance of the examined speech system. This improvement of system performance is the task of the development for the system demonstrator in the 2nd half of the SENECA project

Multimodal Outcomes in N-of-1 Trials: Combining Unsupervised Learning and Statistical Inference

N-of-1 trials are randomized multi-crossover trials in single participants with the purpose of investigating the possible effects of one or more treatments. Research in the field of N-of-1 trials has primarily focused on scalar outcomes. However, with the increasing use of digital technologies, we propose to adapt this design to multimodal outcomes, such as audio, video, or image data or also sensor measurements, that can easily be collected by the trial participants on their personal mobile devices. We present here a fully automated approach for analyzing multimodal N-of-1 trials by combining unsupervised deep learning models with statistical inference. First, we train an autoencoder on all images across all patients to create a lower-dimensional embedding. In the second step, the embeddings are reduced to a single dimension by projecting on the first principal component, again using all images. Finally, we test on an individual level whether treatment and non-treatment periods differ with respect to the component. We apply our proposed approach to a published series of multimodal N-of-1 trials of 5 participants who tested the effect of creams on acne captured through images over 16 days. We compare several parametric and non-parametric statistical tests, and we also compare the results to an expert analysis that rates the pictures directly with respect to their acne severity and applies a t-test on these scores. The results indicate a treatment effect for one individual in the expert analysis. This effect was replicated with the proposed unsupervised pipeline. In summary, our proposed approach enables the use of novel data types in N-of-1 trials while avoiding the need for manual labels. We anticipate that this can be the basis for further explorations of valid and interpretable approaches and their application in clinical multimodal N-of-1 trials.Comment: 11 pages, 4 figure

Active search in intensionally specified structured spaces

We consider an active search problem in intensionally specified structured spaces. The ultimate goal in this setting is to discover structures from structurally different partitions of a fixed but unknown target class. An example of such a process is that of computer-aided de novo drug design. In the past 20 years several Monte Carlo search heuristics have been developed for this process. Motivated by these hand-crafted search heuristics, we devise a Metropolis--Hastings sampling scheme where the acceptance probability is given by a probabilistic surrogate of the target property, modeled with a max entropy conditional model. The surrogate model is updated in each iteration upon the evaluation of a selected structure. The proposed approach is consistent and the empirical evidence indicates that it achieves a large structural variety of discovered targets

Der Text der Statianischen Epen im Spiegel antiker Vorbilder und Imitationen

Analysis of a passage of Statius’ Thebais, where the choice between the variants in P (Paris, BNF, lat. 8051) and the consensus codicum (ω) is difficult. In Theb. 8.554-8 the punctuation may be restored on the basis of Verg. Aen. 2.339-346