Effects of a Problem-based Structure of Physics Contents on Conceptual Learning and the Ability to Solve Problems

A model of teaching/learning is proposed based on a ‘problem-based structure’ of the contents of the course, in combination with a training in paper and pencil problem solving that emphasizes discussion and quantitative analysis, rather than formulae plug-in. The aim is to reverse the high failure and attrition rate among engineering undergraduates taking physics. A number of tests and questionnaires were administered to a group of students following a traditional lecture-based instruction, as well as to another group that was following an instruction scheme based on the proposed approach and the teaching materials developed ad hoc. The results show that students following the new method can develop scientific reasoning habits in problem-solving skills, and show gains in conceptual learning, attitudes and interests, and that the effects of this approach on learning are noticeable several months after the course is over.     

Factors Influencing Schoolchildren's Responses to a Questionnaire in Wildlife Conservation Education

Questionnaires are important tools for assessing attitudes regarding conservation issues. However, they are not easily comparable and their reliability has been insufficiently assessed. We examined factors influencing responses to open- and closed-ended questions about animal conservation to more than 600 schoolchildren (9 years old on average). We analysed the level of understanding, controllable (e.g. sample size) and less controllable factors (e.g. affectivity). Most children responded appropriately to the questions, but subtle changes in the phrasing influenced the answers. Affectivity towards endearing species and spontaneity also influenced the responses whereas small sample sizes (～50 children) provided relatively stable patterns. Overall, we suggest that standardization of questionnaires administered over large spatial and time scales is needed to accurately assess children's attitudes towards conservation issues.     

Public universities and the neoliberal common sense: seven iconoclastic theses

Neoliberalism has utterly failed as a viable model of economic development, yet the politics of culture associated with neoliberalism is still in force, becoming the new common sense shaping the role of government and education. This ‘common sense’ has become an ideology playing a major role in constructing hegemony as moral and intellectual leadership in contemporary societies. Neoliberal globalisation, predicated on the dominance of the market over the state and on deregulatory models of governance, has deeply affected the university in the context of ‘academic capitalism’. The resulting reforms, rationalised as advancing international competitiveness, have affected public universities in four primary areas: efficiency and accountability, accreditation and universalisation, international competitiveness and privatisation. There is also growing resistance to globalisation as top-down-imposed reforms reflected in the public debates about schooling reform, curriculum and instruction, teacher training and school governance. Many question whether neoliberal reforms attempt to limit the effectiveness of universities as sites of contestation of the national and global order and thus undermine the broader goals of education. Neoliberal reforms have limited access and opportunity along class and racial lines, including limiting access to higher education through the imposition of higher tuition and reduced government support to institutions and individuals.     

Adquisición de morfemas del español

Resumen

Se han aplicado dos pruebas de palabras reales y palabras artificiales (semejante a la de Berko, 1958) a 109 niños hispano-parlantes de tres a seis años de edad, a fin de establecer la evolución en el uso de morfemas de plural, aumentativos y diminutivos, gerundio, pretérito imperfecto de indicativo y pretérito indefinido. Los resultados indican un progreso importante entre los tres y los cuatro años, siendo la curva posterior del desarrollo más suave. Se establece un orden de dificultad de estos morfemas, y se realiza un análisis de los errores cometidos, encontrándose también sobrerregularizaciones con verbos reales irregulares. Se extraen implicaciones acerca del proceso de adquisición de morfemas.     

Grade level, study time, and grade retention and their effects on motivation, self-regulated learning strategies, and mathematics achievement: a structural equation model

The present study complements previous research findings with new data to improve our understanding of the relationship between motivational variables and academic performance in math mediated by self-regulated learning (SRL). A structural equation model with predictor (i.e., grade retention, grade level, and study time), process (i.e., perceived usefulness of SRL strategies, self-efficacy for the use of SRL strategies, and reported use of SRL), and product variables (i.e., academic achievement in mathematics) is proposed. The model was analyzed in two samples of data (calibration and validation samples). The first sample served to fit and respecify the model, and the second one was used to analyze the consistency of the findings of the first sample. A sample of 756 middle school Portuguese students participated in the current study. The results indicate that SRL is positively and significantly related to academic achievement and that the latter is, in turn, powerfully determined by perceived usefulness and self-efficacy, although students’ reported use of SRL strategies decreases from 7th to 9th grades. Self-efficacy and perceived usefulness of SRL strategies were also found to decrease as grade retention increased. These results are discussed with regard to the relevance of self-efficacy and perceived usefulness of SRL strategies in increasing academic achievement.     

The Engagement of Older People in Civil Society Organizations

This article reviews recent international literature on the opportunities and restrictions experienced by older people to act as volunteers in civil society organizations. Our aim was to develop a conceptual framework applicable to the European ageing society. This aim was pursued through a computerized database search focused on studies analyzing the individual, organizational, and/or societal levels. Findings show that senior volunteers are characterized by “younger” age, good health, and a high level of both educational and socioeconomical status. Volunteers are involved mainly in religious organizations as well as in social and personal care, while main barriers are represented especially by ageist practices. The review shows that the debate on this topic has been barely developed in Europe, both from an individual and societal point of view. Therefore, European countries might take advantage from experiences made in other contexts, but the identification of how this can occur requires further and more specific cross-national research.     

Using genetic algorithms to evolve a population of topical queries

Systems for searching the Web based on thematic contexts can be built on top of a conventional search engine and benefit from the huge amount of content as well as from the functionality available through the search engine interface. The quality of the material collected by such systems is highly dependant on the vocabulary used to generate the search queries. In this scenario, selecting good query terms can be seen as an optimization problem where the objective function to be optimized is based on the effectiveness of a query to retrieve relevant material. Some characteristics of this optimization problem are: (1) the high-dimensionality of the search space, where candidate solutions are queries and each term corresponds to a different dimension, (2) the existence of acceptable suboptimal solutions, (3) the possibility of finding multiple solutions, and in many cases (4) the quest for novelty. This article describes optimization techniques based on Genetic Algorithms to evolve “good query terms” in the context of a given topic. The proposed techniques place emphasis on searching for novel material that is related to the search context. We discuss the use of a mutation pool to allow the generation of queries with new terms, study the effect of different mutation rates on the exploration of query-space, and discuss the use of a especially developed fitness function that favors the construction of queries containing novel but related terms.     

Correlation analysis of performance measures for multi-label classification

In many important application domains, such as text categorization, scene classification, biomolecular analysis and medical diagnosis, examples are naturally associated with more than one class label, giving rise to multi-label classification problems. This fact has led, in recent years, to a substantial amount of research in multi-label classification. In order to evaluate and compare multi-label classifiers, researchers have adapted evaluation measures from the single-label paradigm, like Precision and Recall; and also have developed many different measures specifically for the multi-label paradigm, like Hamming Loss and Subset Accuracy. However, these evaluation measures have been used arbitrarily in multi-label classification experiments, without an objective analysis of correlation or bias. This can lead to misleading conclusions, as the experimental results may appear to favor a specific behavior depending on the subset of measures chosen. Also, as different papers in the area currently employ distinct subsets of measures, it is difficult to compare results across papers. In this work, we provide a thorough analysis of multi-label evaluation measures, and we give concrete suggestions for researchers to make an informed decision when choosing evaluation measures for multi-label classification.