A bottlenose dolphin discriminates visual stimuli differing in numerosity

A bottlenose dolphin was trained to discriminate two simultaneously presented stimuli differing in numerosity (defined by the number of constituent elements). After responding correctly to stimuli consisting of three-dimensional objects, the dolphin transferred to two-dimensional stimuli. Initially, a variety of stimulus parameters covaried with the numerosity feature. By systematically controlling for these stimulus parameters, it was demonstrated that some of these attributes, such as element configuration and overall brightness, affected the animal’s discrimination performance. However, after all the confounding parameters were under control, the dolphin was able to discriminate the stimuli exclusively on the basis of the numerosity feature. The animal then achieved a successful transfer to novel numerosities, both intervening numerosities and numerosities outside the former range. These findings provide substantial evidence that the dolphin could base his behavior on the numerosity of a set independently of its other attributes and that he represented ordinal relations among numerosities.     

The importance of duration and magnitude of force application to sprint performance during the initial acceleration,transition and maximal velocity phases

ABSTRACT

Successful sprinting depends on covering a specific distance in the shortest time possible. Although external forces are key to sprinting, less consideration is given to the duration of force application, which influences the impulse generated. This study explored relationships between sprint performance measures and external kinetic and kinematic performance indicators. Data were collected from the initial acceleration, transition and maximal velocity phases of a sprint. Relationships were analysed between sprint performance measures and kinetic and kinematic variables. A commonality regression analysis was used to explore how independent variables contributed to multiple-regression models for the sprint phases. Propulsive forces play a key role in sprint performance during the initial acceleration (r = 0.95 ± 0.03) and transition phases (r = 0.74 ± 0.19), while braking duration plays an important role during the transition phase (r = ?0.72 ± 0.20). Contact time, vertical force and peak propulsive forces represented key determinants (r = ?0.64 ± 0.31, r = 0.57 ± 0.35 and r = 0.66 ± 0.30, respectively) of maximal velocity phase performance, with peak propulsive force providing the largest unique contribution to the regression model for step velocity. These results clarified the role of force and time variables on sprinting performance.     

“Muslims are not Terrorists”: Islamic State Coverage,Journalistic Differentiation Between Terrorism and Islam,Fear Reactions,and Attitudes Toward Muslims

Previous research shows that news about Islamist terrorism can seriously affect citizens’ fear reactions and influence non-Muslims’ out-group perceptions of Muslims. We argue that news coverage that explicitly links Islam to terrorism or terrorists of the Islamic State (IS) may trigger fears in non-Muslim individuals. In contrast, news differentiation (i.e., explicitly distinguishing between Muslims and Muslim terrorists) may dampen particular fear reactions in citizens. To test the specific effects of news differentiation, a controlled laboratory experiment was conducted. Results showed that undifferentiated news about IS terrorism increased participants’ fear of terrorism and resulted in hostile perceptions toward Muslims in general. However, fear of terrorism only enhanced hostile attitudes toward Muslims for individuals with negative and moderately positive prior experiences with Muslims. For those with very positive experiences, no such relationship was found. Implications of these findings for journalism practice and intergroup relations in multicultural societies are discussed.     

Changes in ankle work,foot work,and tibialis anterior activation throughout a long run

Background:The ankle and foot together contribute to over half of the positive and negative work performed by the lower limbs during running.Yet,little is known about how foot kinetics change throughout a run.The amount of negative foot work may decrease as tibialis anterior(TA)electromyography(EMG) changes throughout longer-duration runs.Therefore,we examined ankle and foot work as well as TA EMG changes throughout a changing-speed run.Methods:Fourteen heel-striking subjects ran on a treadmill ...     

Introduction to the Special Issue: Using Inquiry-Based Learning in Mathematics for Liberal Arts Courses

Abstract

Mathematics for liberal arts courses are a staple of most mathematics departments and are often populated with students who have disengaged from mathematics. Inquiry-based learning is a student-centered pedagogical tool for re-engaging students in mathematics. In this paper, we introduce a Special Issue of PRIMUS on “Using Inquiry-Based Learning in Mathematics for Liberal Arts Courses.”     

HEIGHTENED TEST ANXIETY AMONG YOUNG CHILDREN: ELEMENTARY SCHOOL STUDENTS’ ANXIOUS RESPONSES TO HIGH‐STAKES TESTING

This study explored differences in test anxiety on high‐stakes standardized achievement testing and low‐stakes testing among elementary school children. This is the first study to directly examine differences in young students’ reported test anxiety between No Child Left Behind (NCLB) achievement testing and classroom testing. Three hundred thirty‐five students in Grades 3 through 5 participated in the study. Students completed assessments of test anxiety following NCLB testing and typical classroom testing. Students reported significantly more overall test anxiety in relation to high‐stakes testing versus classroom testing on two measures of test anxiety, effect sizes r = ?.21 and r = ?.10. Students also reported significantly more cognitive (r = ?.20) and physiological (r = ?.24) symptoms of test anxiety in relation to high‐stakes testing. This study adds to the test anxiety literature by demonstrating that students experience heightened anxiety in response to NCLB testing.     

The Chain and Post-Stratification Methods for Observed-Score Equating: Their Relationship to Population Invariance

The Non-Equivalent-groups Anchor Test (NEAT) design has been in wide use since at least the early 1940s. It involves two populations of test takers, P and Q, and makes use of an anchor test to link them. Two linking methods used for NEAT designs are those (a) based on chain equating and (b) that use the anchor test to post-stratify the distributions of the two operational test scores to a common population (i.e., Tucker equating and frequency estimation). We show that, under different sets of assumptions, both methods are observed score equating methods and we give conditions under which the methods give identical results. In addition, we develop analogues of the Dorans and Holland (2000) RMSD measures of population invariance of equating methods for the NEAT design for both chain and post-stratification equating methods.     

Using Networks to Visualize and Analyze Process Data for Educational Assessment

New technology enables interactive and adaptive scenario‐based tasks (SBTs) to be adopted in educational measurement. At the same time, it is a challenging problem to build appropriate psychometric models to analyze data collected from these tasks, due to the complexity of the data. This study focuses on process data collected from SBTs. We explore the potential of using concepts and methods from social network analysis to represent and analyze process data. Empirical data were collected from the assessment of Technology and Engineering Literacy, conducted as part of the National Assessment of Educational Progress. For the activity sequences in the process data, we created a transition network using weighted directed networks, with nodes representing actions and directed links connecting two actions only if the first action is followed by the second action in the sequence. This study shows how visualization of the transition networks represents process data and provides insights for item design. This study also explores how network measures are related to existing scoring rubrics and how detailed network measures can be used to make intergroup comparisons.     

How to improve argumentation comprehension in university students: experimental test of a training approach

Instructional Science - The ability to comprehend informal arguments is essential for scientific literacy but students often lack structural knowledge about these arguments, especially when the...