Titel Deelnemers "Korte inhoud" """Testing the attention-shift hypothesis as an explanation for flanker sequence-based congruency modulations.""" "Peter Zeischka, N. Deroost, K. Maetens, Eric Soetens" / "Testing the expanded continuum hypothesis of schizophrenia and bipolar disorder : neural and psychological evidence for shared and distinct mechanisms" "Sara Sorellad, Gaia Lapomarda, Irene Messina, Jon Julius Frederickson, Roma Siugzdaite, Remo Job, Alessandro Grecucci" "Despite the traditional view of Schizophrenia (SZ) and Bipolar disorder (BD) as separate diagnostic categories, the validity of such a categorical approach is challenging. In recent years, the hypothesis of a continuum between Schizophrenia (SZ) and Bipolar disorder (BD), postulating a common pathophysiologic mechanism, has been proposed. Although appealing, this unifying hypothesis may be too simplistic when looking at cognitive and affective differences these patients display. In this paper, we aim to test an expanded version of the continuum hypothesis according to which the continuum extends over three clusters: the psychotic, the cognitive, and the affective. We applied an innovative approach known as Source-based Morphometry (SBM) to the structural images of 46 individuals diagnosed with SZ, 46 with BD and 66 healthy controls (HC). We also analyzed the psychological profiles of the three groups using cognitive, affective, and clinical tests. At a neural level, we found evidence for a shared psychotic core in a distributed network involving portions of the medial parietal and temporo-occipital areas, as well as parts of the cerebellum and the middle frontal gyrus. We also found evidence of a cognitive core more compromised in SZ, including alterations in a fronto-parietal circuit, and mild evidence of an affective core more compromised in BD, including portions of the temporal and occipital lobes, cerebellum, and frontal gyrus. Such differences were confirmed by the psychological profiles, with SZ patients more impaired in cognitive tests, while BD in affective ones. On the bases of these results we put forward an expanded view of the continuum hypothesis, according to which a common psychotic core exists between SZ and BD patients complemented by two separate cognitive and affective cores that are both impaired in the two patients' groups, although to different degrees." "Effects of stress and hemispheric preference on job decision making: testing a new hypothesis." "Yori Gidron, Filip Germeys, Antonio Giangreco, O. Leboucher, C. Vanuxem, Yaniv Shani" "No abstract available" "Testing Long memory in the exchange rates and its implications for the adaptive market hypothesis" "Raheel Asif, Michael Frömmel" "Optimal experiment design for hypothesis testing applied to functional magnetic resonance imaging" "X. Bombois, Arjan den Dekker, C.R. Rojas, H. Hjalmarsson, P.M.J. Van den Hof" "Hypothesis testing is a classical methodology of making decisions using experimental data. In hypothesis testing one seeks to discover evidence that either accepts or rejects a given null hypothesis H0. The alternative hypothesis H1 is the hypothesis that is accepted when H0 is rejected. In hypothesis testing, the probability of deciding H1 when in fact H0 is true is known as the false alarm rate, whereas the probability of deciding H1 when in fact H1 is true is known as the detection rate (or power) of the test. It is not possible to optimize both rates simultaneously. In this paper, we consider the problem of determining the data to be used for hypothesis testing that maximize the detection rate for a given false alarm rate. We consider in particular a hypothesis test which is relevant in functional magnetic resonance imaging (fMRI)." "Perturbed datasets methods for hypothesis testing and structure of corresponding confidence sets" "Sandor Kolumban, Istvan Vajk, Joannes Schoukens" "Hypothesis testing methods that do not rely on exact distribution assumptions have been emerging lately. The method of sign-perturbed sums (SPS) is capable of characterizing confidence regions with exact confidence levels for linear regression and linear dynamical systems parameter estimation problems if the noise distribution is symmetric. This paper describes a general family of hypothesis testing methods that have an exact user chosen confidence level based on finite sample count and without relying on an assumed noise distribution. It is shown that the SPS method belongs to this family and we provide another hypothesis test for the case where the symmetry assumption is replaced with exchangeability. In the case of linear regression problems it is shown that the confidence regions are connected, bounded and possibly non-convex sets in both cases. To highlight the importance of understanding the structure of confidence regions corresponding to such hypothesis tests it is shown that confidence sets for linear dynamical systems parameter estimates generated using the SPS method can have non-connected parts, which have far reaching consequences." "Bayesian hypothesis testing for psychologists: A tutorial on the Savage-Dickey method" "Tom Lodewyckx" "In the field of cognitive psychology, the p-value hypothesis test has established a stranglehold on statistical reporting. This is unfortunate, as the p-value provides at best a rough estimate of the evidence that the data provide for the presence of an experimental effect. An alternative and arguably more appropriate measure of evidence is conveyed by a Bayesian hypothesis test, which prefers the model with the highest average likelihood. One of the main problems with this Bayesian hypothesis test, however, is that it often requires relatively sophisticated numerical methods for its computation. Here we draw attention to the Savage-Dickey density ratio method, a method that can be used to compute the result of a Bayesian hypothesis test for nested models and under certain plausible restrictions on the parameter priors. Practical examples demonstrate the method's validity, generality, and flexibility. (C) 2009 Elsevier Inc. All rights reserved." "Chemical hazard prediction and hypothesis testing using quantitative adverse outcome pathways" "Edward J. Perkins, Kaylan Gayen, Jason E. Shoemaker, Philipp Antczak, Lyle Burgoon, Francesco Falciani, Steve Gutsell, Geoff Hodges, Aude Kienzler, Dries Knapen, Mary McBride, Catherine Willett, Francis J. Doyle III, Natàlia Garcia-Reyero" "Current efforts in chemical safety are focused on utilizing human in vitro or alternatives to animal data in a bio­logical pathway context. However, it remains unclear how biological pathways, and toxicology data developed in that context, can be used to quantitatively facilitate decision-making. The objective of this work is to determine if hypothesis testing using adverse outcome pathways (AOPs) can provide quantitative chemical hazard predictions. Current methods for predicting hazards of chemicals in a biological pathway context were extensively reviewed, spe­cific case studies examined, and computational modeling used to demonstrate quantitative hazard prediction based on an AOP. Since AOPs are chemically agnostic, we propose that AOPs function as hypotheses for how specific chemicals may cause adverse effects via specific pathways. Three broad approaches were identified for testing the hypothesis with AOPs, semi-quantitative weight of evidence, probabilistic, and mechanistic modeling. We then demonstrate how these approaches could be used to test hypotheses using high throughput in vitro data and data from alternatives to animal testing. Finally, we discuss standards in development and documentation that would facilitate use in a regu­latory context. We conclude that quantitative AOPs provide a flexible hypothesis framework for predicting chemical hazards, which accommodates a wide range of approaches that are useful at many stages and build upon one another to become increasingly quantitative." "MAP-based code-aided hypothesis testing" "Cedric Herzet, Henk Wymeersch, Frederik Simoens, Marc Moeneclaey, Luc Vandendorpe" "This contribution deals with code-aided hypothesis testing for wireless digital receivers. We provide a theoretical justification for a hypothesis testing algorithm that was previously introduced in [1] based on ad-hoc arguments. Contrary to conventional hypothesis testing methods, the algorithm from [1] exploits the code structure within the received signal and does not require any pilot symbols. By doing so, it allows to improve the bandwidth-efficiency of the transmission. The present contribution shows that, under mild conditions, the performance of the algorithm from [1] coincides with the performance of the optimal Maximum A Posteriori (MAP) hypotesis test. Computer simulations support this result." "English engineer John Smeaton's experimental method(s): Optimisation, hypothesis testing and exploratory experimentation" "Andrew Matthew Alistair Morris" "In this paper I provide a detailed account of eighteenth-century engineer John Smeaton's experimental methods, with the aim of bringing our understanding of his work into line with recent research in the history and philosophy of science. Starting from his use of the technique of parameter variation, I identify three distinct methodological aims in the research he carried out on waterwheels, windmills and hydraulic mortars. These aims are: optimisation, hypothesis testing and maxim generation. The main claim of this paper is that Smeaton did more than merely improve engineering methods by systematising earlier artisanal approaches, which is the classic view of Smeaton's method developed by historians of technology in the 1990s. I argue instead that his approach bridged the divide between science and technology, by integrating both hypothesis testing and exploratory experimentation. This is borne out, in particular, by the way that Smeaton emphasised the exploratory side of the work he published in the Philosophical Transactions, in contrast to his account of the construction of the Eddystone lighthouse, which was aimed at a broader, non-specialist public. I contribute to recent research on exploratory experimentation by showing – in line with other work on this topic – that exploratory experimentation is not incompatible with hypothesis testing. This new perspective on Smeaton's method will hopefully lead to further research and new insights into the relation between science and technology at the start of the Industrial Revolution."