Rasch Measurement v. Item Response Theory: Knowing When to Cross the Line

When students receive the same score on a test, does that mean they know the same amount about the topic? The answer to this question is more complex than it may first appear. This paper compares classical and modern test theories in terms of how they estimate student ability. Crucial distinctions between the aims of Rasch Measurement and IRT are highlighted. By modeling a second parameter (item discrimination) and allowing item characteristic curves to cross, as IRT models do, more information is incorporated into the estimate of person ability, but the measurement scale is no longer guaranteed to have the same meaning for all test takers. We explicate the distinctions between approaches and using a simulation in R (code provided) demonstrate that IRT ability estimates for the same individual can vary substantially in ways that are heavily dependent upon the particular sample of people taking a test whereas Rasch person ability estimates are sample-free and test-free under varying conditions. These points are particularly relevant in the context of standards-based assessment and computer adaptive testing where the aim is to be able to say precisely what all individuals know and can do at each level of ability

Neural correlates of eye contact and social function in autism spectrum disorder

Reluctance to make eye contact during natural interactions is a central diagnostic criterion for autism spectrum disorder (ASD). However, the underlying neural correlates for eye contacts in ASD are unknown, and diagnostic biomarkers are active areas of investigation. Here, neuroimaging, eye-tracking, and pupillometry data were acquired simultaneously using two-person functional near-infrared spectroscopy (fNIRS) during live "in-person" eye-to-eye contact and eye-gaze at a video face for typically-developed (TD) and participants with ASD to identify the neural correlates of live eye-to-eye contact in both groups. Comparisons between ASD and TD showed decreased right dorsal-parietal activity and increased right ventral temporal-parietal activity for ASD during live eye-to-eye contact (p≤0.05, FDR-corrected) and reduced cross-brain coherence consistent with atypical neural systems for live eye contact. Hypoactivity of right dorsal-parietal regions during eye contact in ASD was further associated with gold standard measures of social performance by the correlation of neural responses and individual measures of: ADOS-2, Autism Diagnostic Observation Schedule, 2nd Edition (r = -0.76, -0.92 and -0.77); and SRS-2, Social Responsiveness Scale, Second Edition (r = -0.58). The findings indicate that as categorized social ability decreases, neural responses to real eye-contact in the right dorsal parietal region also decrease consistent with a neural correlate for social characteristics in ASD

The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.Comment: Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figure

Resting state EEG in youth with ASD: age, sex, and relation to phenotype

Background Identification of ASD biomarkers is a key priority for understanding etiology, facilitating early diagnosis, monitoring developmental trajectories, and targeting treatment efforts. Efforts have included exploration of resting state encephalography (EEG), which has a variety of relevant neurodevelopmental correlates and can be collected with minimal burden. However, EEG biomarkers may not be equally valid across the autism spectrum, as ASD is strikingly heterogeneous and individual differences may moderate EEG-behavior associations. Biological sex is a particularly important potential moderator, as females with ASD appear to differ from males with ASD in important ways that may influence biomarker accuracy. Methods We examined effects of biological sex, age, and ASD diagnosis on resting state EEG among a large, sex-balanced sample of youth with (N = 142, 43% female) and without (N = 138, 49% female) ASD collected across four research sites. Absolute power was extracted across five frequency bands and nine brain regions, and effects of sex, age, and diagnosis were analyzed using mixed-effects linear regression models. Exploratory partial correlations were computed to examine EEG-behavior associations in ASD, with emphasis on possible sex differences in associations. Results Decreased EEG power across multiple frequencies was associated with female sex and older age. Youth with ASD displayed decreased alpha power relative to peers without ASD, suggesting increased neural activation during rest. Associations between EEG and behavior varied by sex. Whereas power across various frequencies correlated with social skills, nonverbal IQ, and repetitive behavior for males with ASD, no such associations were observed for females with ASD. Conclusions Research using EEG as a possible ASD biomarker must consider individual differences among participants, as these features influence baseline EEG measures and moderate associations between EEG and important behavioral outcomes. Failure to consider factors such as biological sex in such research risks defining biomarkers that misrepresent females with ASD, hindering understanding of the neurobiology, development, and intervention response of this important population

Precise Measurement of the Neutrino Mixing Parameter theta(23) from Muon Neutrino Disappearance in an Off-Axis Beam

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter theta_{23}. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57 x 10^{20} protons on target, T2K has fit the energy-dependent nu_mu oscillation probability to determine oscillation parameters. Marginalizing over the values of other oscillation parameters yields sin^2 (theta_{23}) = 0.514 +0.055/-0.056 (0.511 +- 0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Delta m^2_{32} = (2.51 +- 0.10) x 10^{-3} eV^2/c^4 (inverted hierarchy: Delta m^2_{13} = (2.48 +- 0.10) x 10^{-3} eV^2/c^4). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty

Measurement of the intrinsic electron neutrino component in the T2K neutrino beam with the ND280 detector

The T2K experiment has reported the first observation of the appearance of electron neutrinos in a muon neutrino beam. The main and irreducible background to the appearance signal comes from the presence in the neutrino beam of a small intrinsic component of electron neutrinos originating from muon and kaon decays. In T2K, this component is expected to represent 1.2% of the total neutrino flux. A measurement of this component using the near detector (ND280), located 280 m from the target, is presented. The charged current interactions of electron neutrinos are selected by combining the particle identification capabilities of both the time projection chambers and electromagnetic calorimeters of ND280. The measured ratio between the observed electron neutrino beam component and the prediction is 1.01 +/- 0.10 providing a direct confirmation of the neutrino fluxes and neutrino cross section modeling used for T2K neutrino oscillation analyses. Electron neutrinos coming from muons and kaons decay are also separately measured, resulting in a ratio with respect to the prediction of 0.68 +/- 0.30 and 1.10 +/- 0.14, respectively

Measurement of the neutrino-oxygen neutral-current interaction cross section by observing nuclear deexcitation gamma rays

We report the first measurement of the neutrino-oxygen neutral-current quasielastic (NCQE) cross section gamma It is obtained by observing nuclear deexcitation. rays which follow neutrino-oxygen interactions at the Super-Kamiokande water Cherenkov detector. We use T2K data corresponding to 3.01 x 10(20) protons on target. By selecting only events during the T2K beam window and with well-reconstructed vertices in the fiducial volume, the large background rate from natural radioactivity is dramatically reduced. We observe 43 events in the 4-30 MeV reconstructed energy window, compared with an expectation of 51.0, which includes an estimated 16.2 background events. The background is primarily nonquasielastic neutral-current interactions and has only 1.2 events from natural radioactivity. The flux-averaged NCQE cross section we measure is 1.55 x 10(-38) cm(2) with a 68% confidence interval of (1.22, 2.20) x 10(-38) cm(2) at a median neutrino energy of 630 MeV, compared with the theoretical prediction of 2.01 x 10(-38) cm(2)

Observation of Electron Neutrino Appearance in a Muon Neutrino Beam

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92 ± 0.55 expected background events. In the PMNS mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm232 and a CP violating phase δCP. In this neutrino oscillation scenario, assuming |Δm232|=2.4×10−3 eV2, sin2θ23=0.5, δCP=0, and Δm232>0 (Δm232<0), a best-fit value of sin22θ13 = 0.140+0.038−0.032 (0.170+0.045−0.037) is obtained

Single-word reading : behavioral and biological perspectives /

As the first title in the new series, 'New Directions in Communication Sciences Research: Integrative Approaches', this volume discusses a unique phenomenon in cognitive science& single-word reading& which is an essential element in successful reading competence. Single-word reading is an interdisciplinary area of research that incorporates phonological, orthographic, graphemic, and semantic information in the representations suitable for the task demands of reading. Editors Elena L. Grigorenko and Adam J. Naples have organized a collection of essays written by an outstanding group of scholars in order to systematically sample research on this important topic, as well as to describe the research within different experimental paradigms. 'Single-Word Reading 'provides an introduction to unfamiliar areas of research, and is an inspiration for future study. The introductory chapter sets up a contextual stage for connections between spoken and written word processing, the stage-based nature of their development, and the role of education. Succeeding chapters address visual word processing; the role of morphology in word recognition; the role of lexical representation; the biological bases of single-word reading and related processes; and more. Reading researchers will take interest in this substantial book, as will professionals and practitioners linked to the teaching of reading in the departments of school psychology, special education, communication disorders, neuroscience, cognitive science, linguistics, and reading.Includes bibliographical references and indexes.Preface / Elena L. Grigorenko and Adam J. Naples -- Foreword / Rhea Paul -- Continuity and discontinuity in the development of single-word reading : theoretical speculations / Philip H.K. Seymour -- The visual skill "reading" / Tatjana A. Nazir and Anke Huckauf -- The development of visual expertise for words : the contribution of electrophysiology / Urs Maurer and Bruce D. McCandliss -- Phonological representations for reading acquisition across languages / Usha Goswami -- The role of morphology in visual word recognition : graded semantic influences due to competing senses and semantic richness of the stem / Laurie Beth Feldman and Dana Basnight-Brown -- Learning words in Zekkish : implications for understanding lexical representation / Lesley Hart and Charles Perfetti -- Cross-code consistency in a functional architecture for word recognition / Jonathan Grainger and Johannes C. Ziegler -- Feedback-consistency effects in single-word reading / Brett Kessler, Rebecca Treiman, and John Mullennix -- Three perspectives on spelling development / Tatiana Cury Pollo, Rebecca Treiman, and Brett Kessler -- Comprehension of single words : the role of semantics in word identification and reading disability / Janice Keenan and Rebecca S. Betjemann -- Single-word reading : perspectives from magnetic source imaging / Pagiotis G. Simos ... [et al.] -- Genetic and environmental influences on word-reading skills / Richard K. Olson -- Molecular genetics of reading / Cathy L. Barr and Jillian M. Couto -- Four "nons" of the brain-genes connection / Elena L. Grigorenko -- Dyslexia : identification and classification / Shayne B. Piasta and Richard K. Wagner -- Fluency training as an alternative intervention for reading-disabled and poor readers / James M. Royer and Rena Walles -- Neurobiological studies of skilled and impaired word reading / Stephen J. Frost ... [et al.] -- Nondeterminism, pleiotropy, and single-word reading : theoretical and practical concerns / James S. MagnusAs the first title in the new series, 'New Directions in Communication Sciences Research: Integrative Approaches', this volume discusses a unique phenomenon in cognitive science& single-word reading& which is an essential element in successful reading competence. Single-word reading is an interdisciplinary area of research that incorporates phonological, orthographic, graphemic, and semantic information in the representations suitable for the task demands of reading. Editors Elena L. Grigorenko and Adam J. Naples have organized a collection of essays written by an outstanding group of scholars in order to systematically sample research on this important topic, as well as to describe the research within different experimental paradigms. 'Single-Word Reading 'provides an introduction to unfamiliar areas of research, and is an inspiration for future study. The introductory chapter sets up a contextual stage for connections between spoken and written word processing, the stage-based nature of their development, and the role of education. Succeeding chapters address visual word processing; the role of morphology in word recognition; the role of lexical representation; the biological bases of single-word reading and related processes; and more. Reading researchers will take interest in this substantial book, as will professionals and practitioners linked to the teaching of reading in the departments of school psychology, special education, communication disorders, neuroscience, cognitive science, linguistics, and reading

Language is spatial”: Experimental evidence for image schemas of concrete and abstract verbs

Cognitive linguistics and experimental psychology have produced tantalizing hints that a substantial portion of language is encoded in the mind in the form of spatial representations that are grounded in perception and action. Researchers represent these spatial aspects using &quot;image schemas &quot; that depict verbs of motion or spatial prepositions via a 2-D layout of generic icons. In two experiments, we tested naïve subjects &apos; intuitions about such image schemas for concrete action verbs as well as abstract action verbs and psychological predicates. A substantial agreement across subjects was observed in both a forced choice task and a free form computer-based drawing task, for both concrete verbs and abstract verbs. In addition to providing support for the generality of image schemas, the data provide a set of norms for future online studies of spatial representations underlying real-time language processing