A study of students' perceptions of the organisation and effectiveness of fieldwork in earth sciences education

This paper reports the findings of a preliminary evaluation of an in-service training programme designed for practising geology/earth science teachers in Portuguese high schools and intended to enhance the effectiveness of fieldwork activities organised by them for their students. Among the points particularly stressed during the in-service training were that students should be adequately prepared for fieldwork through classroom-based activities prior to the fieldwork itself and that to arrive at the maximum educational benefit for the students, they should be involved in collaborative group-based investigation. The findings, derived from an enquiry among students following their exposure to fieldwork, revealed that in both these aspects teachers failed to put theory into practice, probably as the result of a lack of confidence to implement novel procedures. On the positive side, the students reported that they enjoyed the social interaction with other students that the fieldwork made possible and the opportunity to work independently of the teachers.     

A mathematical model for decision-making in the classification of para-footballers with different severity of coordination impairments

Classification is a defining feature of Para-sport, and sports-specific classification systems determined through multidisciplinary scientific research are required, i.e., evidence-based and focused on the relationship between the impairment and the key performance determinants. Data envelopment analysis (DEA) was applied as a classification tool using a directional distance function (DDF) model. The aim of the study was to test the DEA as a possible classification tool in cerebral palsy football. We analyse the performance of 56 international para-footballers with hypertonia, ataxia or athetosis, who completed a 20-test battery with DEA models. Five of the tests are included in the model (change of direction: Illinois agility test; jumping: standing broad jump, four bounds for distance, and triple hop with the non-dominant leg; 10-m sprint/acceleration; and ball dribbling, both in a straight line and following a trajectory), showing that players with less impairment exhibit the highest efficiency. This outcome suggests that DEA models might be feasible for detecting and discriminating the performance and magnitude of impairment in cerebral palsy football, with an objective ranking of the athletes in relation to different physical performance tests. This study also provides reference scores for decision-making during classification and guidance for further research in team Paralympic sports.     

Sincretismo y pensamiento categorial: génesis y diferencias socioculturales

Resumen

El estudio de la representación del mundo en el niño es una de las vías que permiten acercarse a la génesis del pensamiento infantil, a su progresiva estructuración. Interesados en la evolución del sincretismo y del pensamiento categorial, los diálogos con los niños en torno a las ultra-cosas nos han permitido detectar distintos niveles evolutivos dentro del pensamiento sincrétn o y del categorial y nos han puesto en la pista de posibles diferencias socioculturales ligadas con la pertenencia al medio rural o urbano.     

La conceptualización de la vida social escolar

Resumen

El objetivo de este estudio era indagar a qué tipos de conceptos recurren los preadolescentes cuando razonan sobre sucesos ordinarios de la vida social escolar. Brinda trasfondo teórico a la investigación la hipótesis de los dominios de juicio social formulada por Elliot Turiel. Se mantuvo una entrevista de inspiración clínica con 96 alumnos de entre 10 y 16 años, distribuidos en tres grupos de edad. Como estímulos se presentaron cinco episodios representados en tiras de comics. El análisis de los resultados, más cualitativo que cuantitativo, permite detectar la complejidad conceptual de los episodios de la vida ordinaria y la pluralidad de categorías que conforman el conocimiento social; se clarifica también la entidad epistemológica de algunas nociones sociales a la par que algunos cambios de pensamiento asociados con la edad. Se apuntan, por fin, aquellas claves teóricas cuya profundización permitirá acercarse más al sujeto pensante real.     

Retrieving and classifying instances of source code plagiarism

Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.