Children’s tolerance of word-form variation

How much morphological variation can children tolerate when identifying familiar words? This is an important question in the context of the acquisition of richly inflected languages where identical word forms occur far less frequently than in English. To address this question, we compared children’s (N = 96, mean age 4;1, range 2;11–5;1) and adults’ (N = 96, mean age 21 years) tolerance of word-onset modifications (e.g., for stug: wug and wastug) and pseudoaffixes (e.g., kostug and stugko) in a labelextension task. Word-form modifications were repeated within each experiment to establish productive inflectional patterns. In two experiments, children and adults exhibited similar strategies: they were more tolerant of prefixes (wastug) than substitutions of initial consonants (wug), and more tolerant of suffixes (stugko) than prefixes (kostug). The findings point to word-learning strategies as being flexible and adaptive to morphological patterns in languages

Development and Validation of Implicit Measures of Emotional Intelligence Attributes

Emotional intelligence is important for success in a wide range of social and professional roles. Interest in EI has spawned a debate about whether EI should be defined and measured as a set of abilities or as a set of dispositional self-perceptions, the latter being typically assessed with self-report measures that are susceptible to inaccurate self-knowledge and impression management artifacts. This research used Implicit Association Test procedures to develop measures of emotional intelligence and examined their construct validity using a multitrait-multimethod design. The results of confirmatory factor analyses of nested latent trait models provided evidence of convergent and discriminant validity

People are people: a comparative analysis of risk attitudes across Europe

In this paper, we conduct a detailed examination of the determinants of attitudes to financial risk among retail investors in six European countries (Belgium, France, Germany, Italy, Spain and the United Kingdom). We find that respondents from the United Kingdom and Belgium are the most risk tolerant while those from Spain are the least. We observe remarkable similarities in the distributions of risk tolerance across countries despite cultural differences and considerable variations in the extent to which risky investing is undertaken as a routine part of financial planning. We further show that country effects in the cross-sectional variation of attitude to risk scores are swamped by the impacts of gender, salary and wealth, while financial knowledge and prior investment experience are much more important still. Our results have implications for regulators and those who wish to encourage European investors to consider going beyond bank savings and guaranteed products to more prevalent stock market investing in an era of negative real interest rates

Multiple-vehicle resource-constrained navigation in the deep ocean

Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2011.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student submitted PDF version of thesis.Includes bibliographical references (p. 139-148).This thesis discusses sensor management methods for multiple-vehicle fleets of autonomous underwater vehicles, which will allow for more efficient and capable infrastructure in marine science, industry, and naval applications. Navigation for fleets of vehicles in the ocean presents a large challenge, as GPS is not available underwater and dead-reckoning based on inertial or bottom-lock methods can require expensive sensors and suffers from drift. Due to zero drift, acoustic navigation methods are attractive as replacements or supplements to dead-reckoning, and centralized systems such as an Ultra-Short Baseline Sonar (USBL) allow for small and economical components onboard the individual vehicles. Motivated by subsea equipment delivery, we present model-scale proof-of-concept experimental pool tests of a prototype Vertical Glider Robot (VGR), a vehicle designed for such a system. Due to fundamental physical limitations of the underwater acoustic channel, a sensor such as the USBL is limited in its ability to track multiple targets-at best a small subset of the entire fleet may be observed at once, at a low update rate. Navigation updates are thus a limited resource and must be efficiently allocated amongst the fleet in a manner that balances the exploration versus exploitation tradeoff. The multiple vehicle tracking problem is formulated in the Restless Multi-Armed Bandit structure following the approach of Whittle in [108], and we investigate in detail the Restless Bandit Kalman Filters priority index algorithm given by Le Ny et al. in [71]. We compare round-robin and greedy heuristic approaches with the Restless Bandit approach in computational experiments. For the subsea equipment delivery example of homogeneous vehicles with depth-varying parameters, a suboptimal quasi-static approximation of the index algorithm balances low landing error with safety and robustness. For infinite-horizon tracking of systems with linear time-invariant parameters, the index algorithm is optimal and provides benefits of up to 40% over the greedy heuristic for heterogeneous vehicle fleets. The index algorithm can match the performance of the greedy heuristic for short horizons, and offers the greatest improvement for long missions, when the infinite-horizon assumption is reasonably met.by Brooks Louis-Kiguchi Reed.S.M

Effective d=2 supersymmetric Lagrangians from d=1 supermatrix models

We discuss $d=1, {\cal N}=2$ supersymmetric matrix models and exhibit the associated $d=2$ collective field theory in the limit of dense eigenvalues. From this theory we construct, by the addition of several new fields, a $d=2$ supersymmetric effective field theory, which reduces to the collective field theory when the new fields are replaced with their vacuum expectation values. This effective theory is Poincare invariant and contains perturbative and non-perturbative information about the associated superstrings. We exhibit instanton solutions corresponding to the motion of single eigenvalues and discuss their possible role in supersymmetry breaking.Comment: 59 pages. Contains 5 postscript figures included with epsf macro. Figures obtained upon request, preprint CERN-TH.7017/9

Depletion forces near a soft surface

We investigate excluded-volume effects in a bidisperse colloidal suspension near a flexible interface. Inspired by a recent experiment by Dinsmore et al. (Phys. Rev, Lett. 80, 409 (1998)), we study the adsorption of a mesoscopic bead on the surface and show that depletion forces could in principle lead to particle encapsulation. We then consider the effect of surface fluctuations on the depletion potential itself and construct the density profile of a polymer solution near a soft interface. Surprisingly we find that the chains accumulate at the wall, whereas the density displays a deficit of particles at distances larger than the surface roughness. This non-monotonic behavior demonstrates that surface fluctuations can have major repercusions on the properties of a colloidal solution. On average, the additional contribution to the Gibbs adsorbance is negative. The amplitude of the depletion potential between a mesoscopic bead and the surface increases accordingly.Comment: 10 pages, 5 figure

Cohesive Neighborhoods Where Social Expectations Are Shared May Have Positive Impact On Adolescent Mental Health

Adolescent mental health problems are associated with poor health and well-being in adulthood. This study uses data from a birth cohort of children born in large U.S. cities (N=2,264) to examine whether neighborhood collective efficacy (social cohesion and control) is associated with improvements in adolescent mental health. We find that children who grow up in high collective efficacy neighborhoods experience fewer depressive and anxiety symptoms during adolescence than similar children from low collective efficacy neighborhoods. The magnitude of this neighborhood effect is comparable to the effects of depression prevention programs. Findings do not vary by family or neighborhood income, indicating that neighborhood collective efficacy supports adolescent mental health across diverse populations and urban settings. We recommend greater emphasis on neighborhood environments in individual mental health risk assessments and greater investment in community-based initiatives that strengthen neighborhood social cohesion and control