The friction-free weighted price contribution

We introduce a methodology to obtain friction-free estimates of Barclay and Warner’s (1993) Weighted Price Contribution (WPC). With this new approach, we verify recent simulation results suggesting that trading frictions may severely bias the WPC approach. We use high frequency data from a European electronic order-driven market to show that frictions generate a sizable downward bias in the WPC of non-aggressive small-size trades. The bias increases in periods of significant price discovery, and is due to both bid-ask bounce and serial correlation in the quote-midpoint changes. We show that our results extend to the US case.We acknowledge the financial support of the Spanish projects ECO2010-18567 and ECO2011-29751

Evaluating VPIN as a trigger for single-stock circuit breakers

We study if VPIN (Easley et al., 2012a) is an efficient advance indicator of toxicity-induced liquidity crises and related sharp price movements. We find that high VPIN readings rarely signal abnormal illiquidity, and very occasionally anticipate large intraday price changes leading to actual trading halts. We find significant differences in illiquidity and price impact between VPIN-identified toxic and non-toxic halts, but they tend to vanish when we control for ex ante realized volatility. We conclude that the capacity of VPIN to anticipate truly toxic events is limited.This work was supported by the Spanish DGICYT projects ECO2010-18567, ECO2011-29751, ECO2013-4409-P, and ECO2014-58434-P. Roberto Pascual also acknowledges the financial support of Fundación BBVA

Relationship between emotional motivation and academic performance in second language learning

This article presents the results of a research study on the role that affective motivation plays in learning a second language (L2). There were 171 American university students of Spain, German, Italy, and Japan as a second language participated in the study. This was an ex post facto, cross-sectional, and correlational quantitative study that informs us of which is the type of motivation most beneficial for learners and considers variables such as age, gender, academic performance, and the intention to continue studying a second language. An online questionnaire based on the Dörnyei motivational model was administered. The results show that the variables ideal self and “projection of intended effort” of the learners are positively and significantly related to the academic performance of the students and to the intention of enrollment in future foreign language classes. At the opposite extreme, the deontic self or ought-to-self does not correlate significantly with any of the rest of the variables considered. Regarding the cross-sectional analysis of age and gender, no significant differences were found in gender. However, there was a negative and significant correlation between age and academic performance. Furthermore, there was positive and significant correlation between age and projected effort

Carbon monoxide reduces neuropathic pain and spinal microglial activation by inhibiting nitric oxide synthesis in mice

Background: Carbon monoxide (CO) synthesized by heme oxygenase 1 (HO-1) exerts antinociceptive effects during inflammation but its role during neuropathic pain remains unknown. Our objective is to investigate the exact contribution of CO derived from HO-1 in the modulation of neuropathic pain and the mechanisms implicated. Methodology/Principal Findings: We evaluated the antiallodynic and antihyperalgesic effects of CO following sciatic nerve injury in wild type (WT) or inducible nitric oxide synthase knockout (NOS2-KO) mice using two carbon monoxide-releasing molecules (CORM-2 and CORM-3) and an HO-1 inducer (cobalt protoporphyrin IX, CoPP) daily administered from days 10 to 20 after injury. The effects of CORM-2 and CoPP on the expression of HO-1, heme oxygenase 2 (HO-2), neuronal nitric oxide synthase (NOS1) and NOS2 as well as a microglial marker (CD11b/c) were also assessed at day 20 after surgery in WT and NOS2-KO mice. In WT mice, the main neuropathic pain symptoms induced by nerve injury were significantly reduced in a time-dependent manner by treatment with CO-RMs or CoPP. Both CORM-2 and CoPP treatments increased HO-1 expression in WT mice, but only CoPP stimulated HO-1 in NOS2-KO animals. The increased expression of HO-2 induced by nerve injury in WT, but not in NOS2-KO mice, remains unaltered by CORM-2 or CoPP treatments. In contrast, the over-expression of CD11b/c, NOS1 and NOS2 induced by nerve injury in WT, but not in NOS2-KO mice, were significantly decreased by both CORM-2 and CoPP treatments. These data indicate that CO alleviates neuropathic pain through the reduction of spinal microglial activation and NOS1/NOS2 over-expression. Conclusions/Significance: This study reports that an interaction between the CO and nitric oxide (NO) systems is taking place following sciatic nerve injury and reveals that increasing the exogenous (CO-RMs) or endogenous (CoPP) production of CO may represent a novel strategy for the treatment of neuropathic pain

The Effects of Images on Multiple-choice Questions in Computer-based Formative Assessment

Current learning and assessment are evolving into digital systems that can be used, stored, and processed online. In this paper, three different types of questionnaires for assessment are presented. All the questionnaires were filled out online on a web-based format. A study was carried out to determine whether the use of images related to each question in the questionnaires affected the selection of the correct answer. Three questionnaires were used: two questionnaires with images (images used during learning and images not used during learning) and another questionnaire with no images, text-only. Ninety-four children between seven and eight years old participated in the study. The comparison of the scores obtained on the pre-test and on the post-test indicates that the children increased their knowledge after the training, which demonstrates that the learning method is effective. When the post-test scores for the three types of questionnaires were compared, statistically significant differences were found in favour of the two questionnaires with images versus the text-only questionnaire. No statistically significant differences were found between the two types of questionnaires with images. Therefore, to a great extent, the use of images in the questionnaires helps students to select the correct answer. Since this encourages students, adding images to the questionnaires could be a good strategy for formative assessment.

Modelling and Test of an Integrated Magnetic Spring-Eddy Current Damper for Space Applications

This article belongs to the Special Issue Actuators and Dampers for Vibration Control: Damping and Isolation Applications.We present the design, manufacturing, and dynamical characterization of a mechanical suspension made by a passive magnetic spring and an eddy current damper integrated into a single device. Three configurations with 2, 3, and 4 permanent magnets axially distributed with opposite polarizations are designed, simulated, manufactured, and tested. Stiffness of 2410, 2050, 2090 N/m and damping coefficient of 5.45, 10.52 and 17.25 Ns/m are measured for the 2-, 3-, and 4-magnets configurations, respectively. The magnetic suspension provides good mechanical properties combined with excellent cleanness and high reliability, which is very desirable in mechanical systems for space applications.The research leading to these results has received funding from the Spanish Ministerio de Economía y Competitividad under the Plan Estatal de I+D+I 2013-2016, grant agreement no ESP2015-72458-EXP

LULUCF MRV - Analysis and proposals for enhancing Monitoring, Reporting and Verification of greenhouse gases from Land Use, Land Use Change and Forestry in the EU

Land use land use change and forestry sector (LULUCF) is a greenhouse gas inventory (GHG) sector that covers anthropogenic emissions and removals from terrestrial carbon stocks living biomass dead organic matter and soil organic carbon following six main land use categories, Forest land, Cropland, Grassland, Wetlands, Settlements and Other land. According to the United Nation Framework Contract on Climate Change (UNFCCC) all Parties shall report periodically an update inventory of anthropogenic emissions and removals of GHG using comparable methodologies provided by the Intergovernmental Panel on Climate Change (IPCC). Additional requirements exist for reporting and accounting emissions/removals from related direct-human induced activities under the Kyoto Protocol (KP), because its accounting quantities are counted towards an international commitment reduction target. International negotiations have resulted in recent years in the adoption of new rules (e.g. mandatory accounting of Forest management) for the second commitment period of the KP (CP2: 2013-2020). Furthermore, Decision 529/2013/EU, going beyond the international negotiation, added the mandatory accounting of Cropland management and Grassland management. All these changes pose new challenges that MS will need to face from 2015 (i.e. for starting to report during CP2). This report describes the actions undertaken in the context of the Administrative Arrangement “LULUCF MRV” (Monitoring, Reporting, Verification) with DG CLIMA, trough a sequence of tasks (described in detailed in the Annexes). The aim of the AA is to support MS in improving the quality and comparability of LULUCF reporting during CP2, in line with IPCC methods and the new rules at UNFCCC and EU level.JRC.H.3-Forest Resources and Climat

NuIl sex differences in General Intelligence: Evidence from the WAIS-III.

Sin resume

Models on Teaching Effectiveness in Current Scientific Literature

Knowing what defines ‘effective teaching’ contributes significantly to the appropriateness and validity of the instruction provided to pre-service teachers during their initial training. This may help them to perform as expert teachers before finishing their university training. This study aims to reflect upon the most significant models and theoretical contributions of each of the five most common methods for investigating teaching effectiveness in the current scientific literature. To that end, the main scientific sources within this field of study have been obtained on the Internet through the Web of Science (WoS), Scopus and ERIC. The sources were selected for their relevance to the topic, which was determined by assessing the citations generated by the academic works and the impact of the journals in which they were published. The results show that the key and most central factor salient in teaching quality is related to the teachers themselves and their training. Thus, any educational model that seeks educational excellence must focus foremost on ensuring care and respect for teaching professionals, beyond economic investment, resource availability, or any other factors

Tratamiento del desbalance en problemas con múltiples clases con ECOC

El problema del desbalance de clases puede producir un deterioro importante en la efectividad del clasificador, en particular con los patrones de las clases menos representadas. El desbalance en el conjunto de entrenamiento (CE) significa que una clase es representada por una gran cantidad de patrones mientras que otra es representada por muy pocos. Los estudios existentes se encuentran orientados principalmente a tratar problemas de dos clases, no obstante, un importante número de problemas reales se encuentran representados por múltiples clases, donde resulta más difícil su discriminación para el clasificador. El éxito de la Mezcla de Expertos (ME) se basa en el criterio de divide y vencerás. En su funcionamiento general, el problema es dividido en fragmentos más pequeños que serán estudiados por separado. De este modo, el modelo general es poco influenciado por las dificultades individuales de sus componentes. La idea principal del estudio aquí mostrado, es construir una Mezcla de expertos cuyos miembros serán entrenados en una parte del problema general y de este modo, mejorar el rendimiento del clasificador en el contexto de múltiples clases. Para este fin, se hace uso de los métodos conocidos como Error-correcting output codes (ECOC), que permiten realizar una codificación en parejas de clases el problema de estudio. Resultados experimentales sobre conjuntos de datos reales, muestran la viabilidad de la estrategia aquí propuesta