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https://www.lu.se/studera/geologi-masterprogram-NAGEL - 2026-09-19

Finger tapping to isochronous pacing stimuli is a well established experimental paradigm first described in the late 19th century. Two variables of common interest in rhythmic tapping tasks are timing variability and constant error. However, a difficulty when estimating these variables is that at interstimulus intervals longer than 2 seconds participants regularly overshoot the target interval and

The sum of a random number of independent and identically distributed random vectors has a distribution which is not analytically tractable, in the general case. The problem has been addressed by means of asymptotic approximations embedding the number of summands in a stochastically increasing sequence. Another approach relies on fitting flexible and tractable parametric, multivariate distributionThe sum of a random number of independent and identically distributed random vectors has a distribution which is not analytically tractable, in the general case. The problem has been addressed by means of asymptotic approximations embedding the number of summands in a stochastically increasing sequence. Another approach relies on fitting flexible and tractable parametric, multivariate distribution

We propose simple estimation of the location parameter for a density that is unbounded at the mode. The estimator maximizes a modified likelihood in which the singular term in the full likelihood is left out, whenever the parameter value approaches a neighborhood of the singularity location. The consistency and super-efficiency of this maximum leave-one-out likelihood estimator is shown through a

Introduction: It might in the future be valuable to screen for increased maternal arterial stiffness, i.e. low compliance, since it is associated with development of hypertensive complications in pregnancy. Digital pulse wave analysis (DPA) is an easy and manageable method for arterial stiffness assessment. We aimed to investigate gestational influence on DPA variables longitudinally, and establis

Background: Neutrophil gelatinase-associated lipocalin (NGAL) has been suggested as the most promising biomarker of acute kidney injury. However, there are no reliable data on analytical sensitivity and reference limits of urinary NGAL (uNGAL) assay in pediatric age. The aim of the present study is to evaluate the analytical sensitivity and the reference range of uNGAL measured in urine specimens

We consider all two times iterated Ito integrals obtained by pairing m independent standard Brownian motions. First we calculate the conditional joint characteristic function of these integrals, given the Brownian increments over the integration interval, and show that it has a form entirely similar to what is obtained in the univariate case. Then we propose an algorithm for the simultaneous simul

The stochastic Lagrange wave model is a realistic alternative to the Gaussian linear wave model, which has been successfully used in ocean engineering for more than half a century. This paper presents exact slope distributions and other characteristic distributions at level crossings for symmetric and asymmetric Lagrange space and time waves. These distributions are given as expectations in

It was intended with this research to estimate in-sample and out-of-sample Value-at-Risk(VaR) on forwards’ data in Nordic electricity market by using different parametric and nonparametric approaches and investigate which of them give the most accurate results after implementation of back-testing. There were two confidence levels of 95% and 99% used in this research. After implementation of data

Objective: The clinical phenotype of the rare behavioural variant of Alzheimer's disease (bvAD) is insufficiently understood. Given the strong clinico-anatomical correlations of tau pathology in AD, we investigated the distribution of tau deposits in bvAD, in-vivo and ex-vivo, using positron emission tomography (PET) and postmortem examination. Methods: For the tau PET study, seven amyloid-β posit

The introduction of exchange-traded credit default swap (CDS) index futures is eminent and this development in the credit market is the subject of this article. A theoretically appealing and practically implementable approach to computing accurate futures margins based on extreme value theory is suggested. The approach is then exemplified with a study of the increasingly popular iTraxx Europe CDS

This paper will examine the forecast ability of different parametric and non-parametric estimation approaches used for Expected Shortfall (ES). As the financial institutions start to shift towards using ES as a risk measure instead of Value at Risk (VaR), the importance of being able to forecast ES increases. The Paper considers Basic Historical Simulation (BHS), Age-Weighted Historical Simulation

A resampling method for quantitative MRS is presented that retains absolute concentrations. Averaging the spectra from a subset improved the concentrationestimates via increased SNR. Using short-TE STEAM spectra from human thalamus, the influence of subset size was systematically studied and verifiedagainst conventional bootstrap re-sampling. Even small subsets provided considerably better signal-