On the Impact of Features and Classifiers for Measuring Knowledge Gain during Web Search - A Case Study

Search engines are normally not designed to support human learning intents and processes. The ÿeld of Search as Learning (SAL) aims to investigate the characteristics of a successful Web search with a learning purpose. In this paper, we analyze the impact of text complexity of Web pages on predicting knowledge gain during a search session. For this purpose, we conduct an experimental case study and investigate the in˝uence of several text-based features and classiÿers on the prediction task. We build upon data from a study of related work, where 104 participants were given the task to learn about the formation of lightning and thunder through Web search. We perform an extensive evaluation based on a state-of-the-art approach and extend it with additional features related to textual complexity of Web pages. In contrast to prior work, we perform a systematic search for optimal hyperparameters and show the possible in˝uence of feature selection strategies on the knowledge gain prediction. When using the new set of features, state-of-the-art results are noticeably improved. The results indicate that text complexity of Web pages could be an important feature resource for knowledge gain prediction

Editorial: Learning Analytics: Implications for Higher Education

29.03.2017 | Wolfgang Greller & Ulrich Hopp

On the Impact of Features and Classifiers for Measuring Knowledge Gain during Web Search - A Case Study

Search engines are normally not designed to support human learning intents and processes. The field of Search as Learning (SAL) aims to investigate the characteristics of a successful Web search with a learning purpose. In this paper, we analyze the impact of text complexity of Web pages on predicting knowledge gain during a search session. For this purpose, we conduct an experimental case study and investigate the influence of several text-based features and classifiers on the prediction task. We build upon data from a study of related work, where 104 participants were given the task to learn about the formation of lightning and thunder through Web search. We perform an extensive evaluation based on a state-of-the-art approach and extend it with additional features related to textual complexity of Web pages. In contrast to prior work, we perform a systematic search for optimal hyperparameters and show the possible influence of feature selection strategies on the knowledge gain prediction. When using the new set of features, state-of-the-art results are noticeably improved. The results indicate that text complexity of Web pages could be an important feature resource for knowledge gain prediction

Formative assessment strategies for students' conceptions—The potential of learning analytics

Formative assessment is considered to be helpful in students' learning support and teaching design. Following Aufschnaiter's and Alonzo's framework, formative assessment practices of teachers can be subdivided into three practices: eliciting evidence, interpreting evidence and responding. Since students' conceptions are judged to be important for meaningful learning across disciplines, teachers are required to assess their students' conceptions. The focus of this article lies on the discussion of learning analytics for supporting the assessment of students' conceptions in class. The existing and potential contributions of learning analytics are discussed related to the named formative assessment framework in order to enhance the teachers' options to consider individual students' conceptions. We refer to findings from biology and computer science education on existing assessment tools and identify limitations and potentials with respect to the assessment of students' conceptions. Practitioner notes What is already known about this topic Students' conceptions are considered to be important for learning processes, but interpreting evidence for learning with respect to students' conceptions is challenging for teachers. Assessment tools have been developed in different educational domains for teaching practice. Techniques from artificial intelligence and machine learning have been applied for automated assessment of specific aspects of learning. What does the paper add Findings on existing assessment tools from two educational domains are summarised and limitations with respect to assessment of students' conceptions are identified. Relevent data that needs to be analysed for insights into students' conceptions is identified from an educational perspective. Potential contributions of learning analytics to support the challenging task to elicit students' conceptions are discussed. Implications for practice and/or policy Learning analytics can enhance the eliciting of students' conceptions. Based on the analysis of existing works, further exploration and developments of analysis techniques for unstructured text and multimodal data are desirable to support the eliciting of students' conceptions

Comparing Interface Layouts for the Presentation of Multimodal Search Results

Today's search engines allow users to discover relevant information in different types of modalities or media, e.g., web pages, text documents, images, or videos. It is, however, a challenging task to present mixed-modality result lists in an effective and easy-to-skim form. The two most commonly used approaches are to present the modalities side-by-side, each in a separate column of the result page; or to separate the modalities into multiple tabs. However, the field lacks a structured investigation on how the column or tab layout influence the users' perception and usage of multimodal resources in an academic search task. In this paper, we present a user study (N=50) where the participants were asked to accomplish a search task for a fictive computer science seminar at the university. We evaluate the influence of the different layouts on (1) user search behavior (e.g., time until first resource is saved) and (2) the relevance of the selected resources for the task at hand. Finally, we discuss the results and possible implications for the design of multimodal search result presentation

VAMPIR: Visualization and Analysis of MPI Resources

Performance analysis most often is based on the detailed knowledge of program behavior. One option to get this information is tracing. Based on the research tool PARvis, the visualization environment VAMPIR was developed at KFA which now supports the new message passing standard MPI. VAMPIR translates a given trace file into a variety of graphical views, e.g., state diagrams, activity charts, time-line displays, and statistics. Moreover, it supports an animation mode that can help to locate performance bottlenecks, and it provides flexible filter operations to reduce the amount of information displayed. The most interesting part of VAMPIR is the powerful zooming feature that allows to identify problems at any level of detail

Elevated impulsivity and impaired decision-making cognition in heavy users of MDMA ("Ecstasy”)

Rationale: In animal studies, the common club drug 3,4-methylendioxymethamphetamine (MDMA, "Ecstasy”) consistently caused a prolonged loss of presynaptic serotonergic neurons, and evidence suggests that MDMA consumption may also affect the human serotonergic system. Serotonin (5-HT) has been implicated in the regulation of impulsivity and such executive functions as decision-making cognition. In fact, MDMA users have shown elevated impulsivity in two studies, but little is known about decision making in drug-free MDMA consumers. Objective: The aim of this study was to examine the cognitive neurotoxicity of MDMA with regard to behavioral impulsivity and decision-making cognition. Methods: Nineteen male, abstinent, heavy MDMA users; 19 male, abstinent cannabis users; and 19 male, drug-naïve controls were examined with the Matching Familiar Figures Test (MFFT) as well as with a Go/No-Go Task (GNG) for impulsivity and with a Gambling Task (GT) for executive functioning. Results: MDMA users showed significantly elevated impulsivity in the MFFT Impulsivity score (I-score), but not in commission errors of the GNG, compared with controls. Cannabis users did not yield altered impulsivity compared with controls. In the GT, MDMA users performed significantly worse than cannabis consumers and controls, whereas cannabis users exhibited the same decision-making capacity as controls. In addition, the I-score as well as the decision-making performance was correlated with measures of MDMA intake. The I-score and the decision-making performance were also correlated. Conclusion: These results suggest that heavy use of MDMA may elevate behavioral impulsivity and impair decision-making cognition possibly mediated by a selective impairment of the 5-HT syste

O palácio das ilusões da tradução austeniana : “Orgulho e preconceito” no sistema literário

Nas décadas de 1930 e 1940, o mercado editorial brasileiro passou por sérias crises e mudanças, as quais acabaram contribuindo para o crescimento da tradução no país, transformando essas décadas na Era de Ouro da tradução. Esta pesquisa, vinculada ao projeto “Tradução e sistema literário – história da tradução no Brasil: a tradução dos clássicos e os escritores/tradutores”, objetiva investigar esse período e sua importância para a história da tradução no Brasil, juntamente com o lugar ocupado pela Editora José Olympio nesse contexto com relação aos clássicos literários estrangeiros traduzidos por autores brasileiros. Em um segundo momento, analisaremos as traduções de duas das obras de Jane Austen publicadas pela José Olympio na Coleção Fogos Cruzados, Orgulho e preconceito, traduzida por Lúcio Cardoso, em 1941, e Mansfield Park, traduzida por Rachel de Queiroz, em 1942. Será feito um estudo comparativo das obras com suas traduções mais recentes, a de Orgulho e preconceito por Alexandre Barbosa de Souza (Penguin Companhia, 2011), e a de Mansfield Park de Mariana Menezes Neumann (BestBolso, 2011). Com isso, pretendemos analisar a apresentação da obra traduzida em relação à sua economia estética e aos paratextos editoriais.During the 1930’s and 1940’s, the Brazilian publishing industry experienced many crisis and changes that, surprisingly as it may be, contributed to the development of the translation practice in Brazil, making of these decades the Golden Age of translation. This research project is part of a major project, “Translation and literary system – the history of translation in Brazil: translation of canons and the writers/translators”, and aimed to investigate this period of time and its importance to the Brazilian translation history. It also studied the role of the Editora José Olympio in this context, regarding the translations of literary classics by Brazilian writers. After that, we analyzed the translations of two of Jane Austen’s titles that have been published by the Editora José Olympio in the Fogos Cruzados Collection, Pride and Prejudice, translated by Lúcio Cardoso, 1941, and Mansfield Park, translated by Rachel de Queiroz, 1942. We conducted a comparative study between these titles and their most recent translations: Pride and Prejudice, translated by Alexandre Barbosa de Souza (Penguin Companhia, 2011), and Mansfield Park, translated by Mariana Menezes Neumann (BestBolso, 2011). By doing this, we aimed to analyze the way these texts were presented to public, regarding its aesthetics and paratexts

Atomic Scale Control of Spin Current Transmission at Interfaces

Ferromagnet/heavy metal bilayers represent a central building block for spintronic devices where the magnetization of the ferromagnet can be controlled by spin currents generated in the heavy metal. The efficiency of spin current generation is paramount. Equally important is the efficient transfer of this spin current across the ferromagnet/heavy metal interface. Here, we show theoretically and experimentally that for Ta as heavy metal the interface only partially transmits the spin current while this effect is absent when Pt is used as heavy metal. This is due to magnetic moment reduction at the interface caused by 3d–5d hybridization effects. We show that this effect can be avoided by atomically thin interlayers. On the basis of our theoretical model we conclude that this is a general effect and occurs for all 5d metals with less than half-filled 5d shell