Simultaneous interval regression for K-nearest neighbor

International audienceIn some regression problems, it may be more reasonable to predict intervals rather than precise values. We are interested in finding intervals which simultaneously for all input instances x ∈X contain a β proportion of the response values. We name this problem simultaneous interval regression. This is similar to simultaneous tolerance intervals for regression with a high confidence level γ ≈ 1 and several authors have already treated this problem for linear regression. Such intervals could be seen as a form of confidence envelop for the prediction variable given any value of predictor variables in their domain. Tolerance intervals and simultaneous tolerance intervals have not yet been treated for the K-nearest neighbor (KNN) regression method. The goal of this paper is to consider the simultaneous interval regression problem for KNN and this is done without the homoscedasticity assumption. In this scope, we propose a new interval regression method based on KNN which takes advantage of tolerance intervals in order to choose, for each instance, the value of the hyper-parameter K which will be a good trade-off between the precision and the uncertainty due to the limited sample size of the neighborhood around each instance. In the experiment part, our proposed interval construction method is compared with a more conventional interval approximation method on six benchmark regression data sets

LD Hub:a centralized database and web interface to perform LD score regression that maximizes the potential of summary level GWAS data for SNP heritability and genetic correlation analysis

Motivation: LD score regression is a reliable and efficient method of using genome-wide association study (GWAS) summary-level results data to estimate the SNP heritability of complex traits and diseases, partition this heritability into functional categories, and estimate the genetic correlation between different phenotypes. Because the method relies on summary level results data, LD score regression is computationally tractable even for very large sample sizes. However, publicly available GWAS summary-level data are typically stored in different databases and have different formats, making it difficult to apply LD score regression to estimate genetic correlations across many different traits simultaneously. Results: In this manuscript, we describe LD Hub - a centralized database of summary-level GWAS results for 173 diseases/traits from different publicly available resources/consortia and a web interface that automates the LD score regression analysis pipeline. To demonstrate functionality and validate our software, we replicated previously reported LD score regression analyses of 49 traits/diseases using LD Hub; and estimated SNP heritability and the genetic correlation across the different phenotypes. We also present new results obtained by uploading a recent atopic dermatitis GWAS meta-analysis to examine the genetic correlation between the condition and other potentially related traits. In response to the growing availability of publicly accessible GWAS summary-level results data, our database and the accompanying web interface will ensure maximal uptake of the LD score regression methodology, provide a useful database for the public dissemination of GWAS results, and provide a method for easily screening hundreds of traits for overlapping genetic aetiologies

Astroparticle Physics with a Customized Low-Background Broad Energy Germanium Detector

The MAJORANA Collaboration is building the MAJORANA DEMONSTRATOR, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The MAJORANA DEMONSTRATOR will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1-10 GeV/c^2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the MAJORANA Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.Comment: Submitted to NIMA Proceedings, SORMA XII. 9 pages, 4 figure

Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review

Search for supersymmetry in final states with jets, missing transverse momentum and one isolated lepton in sqrt{s} = 7 TeV pp collisions using 1 fb-1 of ATLAS data

We present an update of a search for supersymmetry in final states containing jets, missing transverse momentum, and one isolated electron or muon, using 1.04 fb^-1 of proton-proton collision data at sqrt{s} = 7 TeV recorded by the ATLAS experiment at the LHC in the first half of 2011. The analysis is carried out in four distinct signal regions with either three or four jets and variations on the (missing) transverse momentum cuts, resulting in optimized limits for various supersymmetry models. No excess above the standard model background expectation is observed. Limits are set on the visible cross-section of new physics within the kinematic requirements of the search. The results are interpreted as limits on the parameters of the minimal supergravity framework, limits on cross-sections of simplified models with specific squark and gluino decay modes, and limits on parameters of a model with bilinear R-parity violation.Comment: 18 pages plus author list (30 pages total), 9 figures, 4 tables, final version to appear in Physical Review

Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

This paper constructs the reduction of heterotic $M$-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe

Measurement of tau polarization in W->taunu decays with the ATLAS detector in pp collisions at sqrt(s) = 7 TeV

In this paper, a measurement of tau polarization in W->taunu decays is presented. It is measured from the energies of the decay products in hadronic tau decays with a single final state charged particle. The data, corresponding to an integrated luminosity of 24 pb^-1, were collected by the ATLAS experiment at the Large Hadron Collider in 2010. The measured value of the tau polarization is Ptau = -1.06 +/- 0.04 (stat) + 0.05 (syst) - 0.07 (syst), in agreement with the Standard Model prediction, and is consistent with a physically allowed 95% CL interval [-1,-0.91]. Measurements of tau polarization have not previously been made at hadron colliders.Comment: 10 pages plus author list (25 pages total), 4 figures, 4 tables, revised author list, matches published EPJC versio

Readiness of the ATLAS liquid argon calorimeter for LHC collisions

The ATLAS liquid argon calorimeter has been operating continuously since August 2006. At this time, only part of the calorimeter was readout, but since the beginning of 2008, all calorimeter cells have been connected to the ATLAS readout system in preparation for LHC collisions. This paper gives an overview of the liquid argon calorimeter performance measured in situ with random triggers, calibration data, cosmic muons, and LHC beam splash events. Results on the detector operation, timing performance, electronics noise, and gain stability are presented. High energy deposits from radiative cosmic muons and beam splash events allow to check the intrinsic constant term of the energy resolution. The uniformity of the electromagnetic barrel calorimeter response along eta (averaged over phi) is measured at the percent level using minimum ionizing cosmic muons. Finally, studies of electromagnetic showers from radiative muons have been used to cross-check the Monte Carlo simulation. The performance results obtained using the ATLAS readout, data acquisition, and reconstruction software indicate that the liquid argon calorimeter is well-prepared for collisions at the dawn of the LHC era.ATLAS Collaboration, for complete list of authors see http://dx.doi.org/10.1140/epjc/s10052-010-1354-y</p

Псориаз: клинико-эпидемиологические особенности и вопросы терапии

Aim. This study sets out to establish the demographic and clinical features of psoriasis and its co-morbidities; to describe approaches to treating patients in Russia, to whom the systemic therapy of drugs has been recommended; to assess the effects of this dermatosis on the patients' quality of life and work productivity; to assess the degree of consistency between dermatologists' and patients' estimates concerning the severity of the disease, complaints/objective manifestations and treatment satisfaction.Methods. Data from the GfK Disease Atlas was used. This ATLAS was filed within a global programme Growth from Knowledge that collected reliable data in the context of everyday clinical practice in 9 countries. The paper presents the results solely for the Russian sample. The study involved patients with moderate or severe psoriasis who were receiving systemic therapy for this disease. Using specially developed forms, ATLAS specialists registered data about patients, their disease and received treatment. The patients affected by psoriasis, who participated in the study, were questioned about their disease. Dermatologists assessed the severity of psoriasis, the patients' complaints, co-morbidities and received treatment. The patients completed questionnaires aimed at assessing the quality of their life [Dermatology Life Quality Index, DLQI] and their work productivity [Work Productivity and Activity Impairment, WPAI]. The concordance between the patients' and the dermatologists' estimates was assessed using Cohen's kappa coefficient.Results. Overall, 3,821 patients participated in the ATLAS programme, out of whom 300 patients were Russians. The average time since psoriasis diagnosis amounted to 9.9 years. 51 % of the patients complained about itching in the lesion areas. Psoriatic arthritis was registered in 19 % of the cases. Among co-morbidities, anxiety or depression was most often recorded (11 %, respectively). The proportion of patients with pruritus and related comorbid conditions increased with psoriasis severity. The disease negatively affected the quality of patients’ life (the average value of DLQI was 7.1) and their work productivity (a decrease in the work productivity reached 33.2 %), with these indicators deteriorating with psoriasis severity. Despite the dominance of moderate and severe psoriasis forms among the participants, 60 % of the patients received therapy only with topical medications. The concordance rate between the patients and the dermatologists concerning the estimation of psoriasis severity and treatment satisfaction was low.Conclusion. Despite the therapy with systemic drugs, the patients' quality of life affected by severe or moderate psoriasis forms remained low. The consistency between the views on the treatment success between the patients and the dermatologists was low.Цель: Установить демографические и клинические характеристики псориаза, коморбидных ему состояний и подходы к лечению российских пациентов, которым была показана терапия системными препаратами; оценить влияние данного дерматоза на качество жизни и работоспособность пациентов, а также оценить степень согласованности оценок о тяжести заболевания, жалоб/объективных проявлений и удовлетворенности лечением псориаза между пациентами и дерматологами.Методы. Использовались данные, полученные в Глобальной программе сбора доказательных данных в условиях повседневной клинической практики Growth from Knowledge (GfK) Disease ATLAS, проводившейся в девяти странах. В работе представлены результаты только по российской выборке. В исследовании участвовали пациенты со среднетяжелым или тяжелым псориазом, которые получали системную терапию по поводу данного заболевания. В рамках наблюдательной программы ATLAS специалисты регистрировали данные о пациентах, их заболевании и проводимом лечении в специально разработанных формах. Больные псориазом, участвовавшие в исследовании, самостоятельно отвечали на вопросы о своем заболевании. Дерматологами оценивались тяжесть псориаза, имеющиеся жалобы, коморбидности и проводимое лечение, в то время как пациенты заполняли опросники по оценке качества жизни и работоспособности (дерматологический индекс качества жизни [Dermatology Life Quality Index, DLQI] и опросник производительности труда и повседневной активности [Work Productivity and Activity Impairment, WPAI] соответственно). Конкордантность оценок пациентов и дерматологов оценивалась по каппа-коэффициенту Коэна.Результаты: Всего в программе ATLAS в мире участвовали 3821 пациент, из которых 300 были российскими. Среднее время с момента постановки диагноза псориаза составило 9,9 года. 51 % пациентов предъявляли жалобы на зуд в очагах поражения. Псориатический артрит зарегистрирован в 19 % случаев. Среди коморбидностей наиболее часто регистрировали тревожность либо депрессия (11 % соответственно). Доля пациентов с зудом и сопутствующими коморбидными состояниями увеличивалась по мере нарастания тяжести псориаза. Заболевание отрицательно сказывалось на качестве жизни пациентов (среднее значение DLQI 7,1) и работоспособности (снижение работоспособности составило 33,2 %), причем данные показатели ухудшались по мере нарастания тяжести заболевания. Несмотря на доминирование среднетяжелых и тяжелых форм псориаза у участников исследования, 60 % пациентов получали только терапию топическими лекарственными средствами. Установленная степень конкордантности между пациентами и дерматологами по оценке тяжести псориаза и общей удовлетворенности достигнутыми результатами проводимой терапии была низкой.Вывод. Несмотря на проводимую терапию системными препаратами, качество жизни пациентов с тяжелым и среднетяжелым псориазом оставалась сниженной. Согласованность представлений об успешности результатов лечения данного дерматоза между пациентами и дерматологами была низкой

Glyphosate, Other Herbicides, And Transformation Products In Midwestern Streams, 2002

The use of glyphosate has increased rapidly, and there is limited understanding of its environmental fate. The objective of this study was to document the occurrence of glyphosate and the transformation product aminomethylphosphonic acid (AMPA) in Midwestern streams and to compare their occurrence with that of more commonly measured herbicides such as acetochlor, atrazine, and metolachlor. Water samples were collected at sites on 51 streams in nine Midwestern states in 2002 during three runoff events: after the application of pre-emergence herbicides, after the application of post-emergence herbicides, and during harvest season. All samples were analyzed for glyphosate and 20 other herbicides using gas chromatography/mass spectrometry or high performance liquid chromatography/mass spectrometry. The frequency of glyphosate and AMPA detection, range of concentrations in runoff samples, and ratios of AMPA to glyphosate concentrations did not vary throughout the growing season as substantially as for other herbicides like atrazine, probably because of different seasonal use patterns. Glyphosate was detected at or above 0.1 μg/l in 35 percent of pre-emergence, 40 percent of post-emergence, and 31 percent of harvest season samples, with a maximum concentration of 8.7 μg/l. AMPA was detected at or above 0.1 μg/l in 53 percent of pre-emergence, 83 percent of post-emergence, and 73 percent of harvest season samples, with a maximum concentration of 3.6 μg/l. Glyphosate was not detected at a concentration at or above the U.S. Environmental Protection Agency’s maximum contamination level (MCL) of 700 μg/l in any sample. Atrazine was detected at or above 0.1 μg/l in 94 percent of pre-emergence, 96 percent of postemergence, and 57 percent of harvest season samples, with a maximum concentration of 55 μg/l. Atrazine was detected at or above its MCL (3 μg/l) in 57 percent of pre-emergence and 33 percent of postemergence samples