Nonparametric Identification and Estimation of Multi-Unit, Sequential, Oral, Ascending-Price Auctions With Asymmetric Bidders

Within the independent private-values paradigm, we derive the data-generating process of the winning bid for the last unit sold at multi-unit sequential English auctions when bidder valuations are draws from different distributions; i.e., in the presence of asymmetries. When the identity of the winner as well as the number of units won by each bidder in previous stages of the auction are observed, we demonstrate nonparametric identification and then propose two estimation strategies, one based on the empirical distribution function of winning bids for the last unit sold and the other based on approximation methods using orthogonal polynomials. We apply our methods to daily data from fish auctions held in Grenå, Denmark. For single-unit supply, we use our estimates to compare the revenues a seller could expect to earn were a Dutch auction employed instead.Asymmetric, Multi-unit, Sequential, Oral, Ascending-price fish auctions, Dutch auctions, Nonparametric identification and estimation

Impact of SDN Controllers Deployment on Network Availability

Software-defined networking (SDN) promises to improve the programmability and flexibility of networks, but it may bring also new challenges that need to be explored. The purpose of this technical report is to assess how the deployment of the SDN controllers affects the overall availability of SDN. For this, we have varied the number, homing and location of SDN controllers. A two-level modelling approach that is used to evaluate the availability of the studied scenarios. Our results show how network operators can use the approach to find the optimal cost implied by the connectivity of the SDN control platform by keeping high levels of availability.Comment: Department of Telematics, NTNU, Tech. Rep., March 201

CO2 emission reduction by exploitation of rolling resistance modelling of pavements

AbstractApproximately one third of the Danish CO2 emissions come from the transport sector, whereof 95% is related to road transport emission. A reduction of the fuel consumption by approximately 3.3% on the road infrastructure will result in 48 million litres of saved fuel and 45.000 tons less greenhouse gases per year. Energy saving road pavements will therefore contribute to Denmark's quota in reaching the global climatic goals. The Cooee project addresses CO2 emission reduction by considering energy efficient and environmentally friendly transport systems and maintenance of the road infrastructure. By doing so, the Cooee consortium will exploit the research results in management of the Danish road infrastructure. To contribute to a sustainable Danish road infrastructure by reducing CO2-emission in a cost-effective manner, Cooee addresses the following: 1. Novel pavements with low rolling resistance, 2. Models of rolling resistance, 3. Wear and ageing of pavements, 4. Measurements of rolling resistance, 5. Asset management systems. The Cooee project is a collaboration between the Danish Road Directorate, Roskilde University, the Technical University of Denmark and NCC Roads. The Danish Strategic Research Council granted in 2011 2 million EUR to the Cooee project. The Cooee project plans to create two models: A comprehensive model of the contact zone between the tyre and the pavement, and a model for the pavement material. When these are in place, performance and optimization models will be established and implemented in the Danish asset management system “vejman.dk”. This will enable the Danish Road Directorate to include CO2-emission as a parameter in its strategic planning and maintenance of the Danish state roads. This paper presents the outline of the project, its expected results and the status

Engagement of Students Teaching Assistants-Confessions From 5 Years of Conference Participation

This paper reports from five years of experience of engaging young student teaching assistants in the continuous development of a course by involving them in research, both pedagogically and in other course related themes. The purpose of the paper is to pave the road for a more engaged and integrated form of teaching, where the full potential of STAs is released. Firstly some basic constructs are presented; secondly a concrete example of STAs’ research activity is presented - as an illustrative case - which also forms the empirical background of the paper. Finally implications and reflections are identified accompanied with suggestions for further research

The Distance to the Coma Cluster from Surface Brightness Fluctuations

We report on the first determination of the distance to the Coma Cluster based on surface brightness fluctuation (SBF) measurements obtained from Hubble Space Telescope WFPC2 observations of the bright E0 galaxy NGC 4881 in the Coma Cluster and ground-based observations of the standard E1 galaxy NGC 3379 in the Leo-I group. Relative distances based on the I-band fluctuation magnitude, I(SBF), are strongly dependent on metallicity and age of the stellar population. However, the radial changes in the stellar populations of the two giant ellipticals, NGC 3379 and NGC 4881, are well described by published Mg_2 gradients, and the ground-based measurements of I(SBF) at several radial points in NGC 3379 are used to calibrate I(SBF) in terms of the Mg_2 index. The distance to NGC 3379, assumed to be identical to the average SBF distance of the Leo-I group, is combined with the new SBF measurements of NGC 4881 to obtain a Coma Cluster distance of 102+-14 Mpc. Combining this distance with the cosmic recession velocity of Coma (7186+-428 km/s), we find the Hubble constant to be H_0 = 71+-11 km/s/Mpc.Comment: 12 pages, LaTex, includes aaspp4.sty and 3 eps figures. To appear in ApJ Letter

Consanguinity and rare mutations outside of MCCC genes underlie nonspecific phenotypes of MCCD.

Purpose3-Methylcrotonyl-CoA carboxylase deficiency (MCCD) is an autosomal recessive disorder of leucine catabolism that has a highly variable clinical phenotype, ranging from acute metabolic acidosis to nonspecific symptoms such as developmental delay, failure to thrive, hemiparesis, muscular hypotonia, and multiple sclerosis. Implementation of newborn screening for MCCD has resulted in broadening the range of phenotypic expression to include asymptomatic adults. The purpose of this study was to identify factors underlying the varying phenotypes of MCCD.MethodsWe performed exome sequencing on DNA from 33 cases and 108 healthy controls. We examined these data for associations between either MCC mutational status, genetic ancestry, or consanguinity and the absence or presence/specificity of clinical symptoms in MCCD cases.ResultsWe determined that individuals with nonspecific clinical phenotypes are highly inbred compared with cases that are asymptomatic and healthy controls. For 5 of these 10 individuals, we discovered a homozygous damaging mutation in a disease gene that is likely to underlie their nonspecific clinical phenotypes previously attributed to MCCD.ConclusionOur study shows that nonspecific phenotypes attributed to MCCD are associated with consanguinity and are likely not due to mutations in the MCC enzyme but result from rare homozygous mutations in other disease genes.Genet Med 17 8, 660-667

Panorama of the distal myopathies

Distal myopathies are genetic primary muscle disorders with a prominent weakness at onset in hands and/or feet. The age of onset (from early childhood to adulthood), the distribution of muscle weakness (upper versus lower limbs) and the histological findings (ranging from nonspecific myopathic changes to myofibrillar disarrays and rimmed vacuoles) are extremely variable. However, despite being characterized by a wide clinical and genetic heterogeneity, the distal myopathies are a category of muscular dystrophies: genetic diseases with progressive loss of muscle fibers. Myopathic congenital arthrogryposis is also a form of distal myopathy usually caused by focal amyoplasia. Massive parallel sequencing has further expanded the long list of genes associated with a distal myopathy, and contributed identifying as distal myopathy-causative rare variants in genes more often related with other skeletal or cardiac muscle diseases. Currently, almost 20 genes (ACTN2, CAV3, CRYAB, DNAJB6, DNM2, FLNC, HNRNPA1, HSPB8, KHLH9, LDB3, MATR3, MB, MYOT, PLIN4, TIA1, VCP, NOTCH2NLC, LRP12, GIPS1) have been associated with an autosomal dominant form of distal myopathy. Pathogenic changes in four genes (ADSSL, ANO5, DYSF, GNE) cause an autosomal recessive form; and disease-causing variants in five genes (DES, MYH7, NEB, RYR1 and TTN) result either in a dominant or in a recessive distal myopathy. Finally, a digenic mechanism, underlying a Welander-like form of distal myopathy, has been recently elucidated. Rare pathogenic mutations in SQSTM1, previously identified with a bone disease (Paget disease), unexpectedly cause a distal myopathy when combined with a common polymorphism in TIA1. The present review aims at describing the genetic basis of distal myopathy and at summarizing the clinical features of the different forms described so far. ©2020 Gaetano Conte Academy - Mediterranean Society of Myology, Naples, Italy.Peer reviewe