Linear feature extraction for ranking

We address the feature extraction problem for document ranking in information retrieval. We then propose LifeRank, a Linear feature extraction algorithm for Ranking. In LifeRank, we regard each document collection for ranking as a matrix, referred to as the original matrix. We try to optimize a transformation matrix, so that a new matrix (dataset) can be generated as the product of the original matrix and a transformation matrix. The transformation matrix projects high-dimensional document vectors into lower dimensions. Theoretically, there could be very large transformation matrices, each leading to a new generated matrix. In LifeRank, we produce a transformation matrix so that the generated new matrix can match the learning to rank problem. Extensive experiments on benchmark datasets show the performance gains of LifeRank in comparison with state-of-the-art feature selection algorithms.     

A selective analysis of empirical findings in networked learning research in higher education: Questing for coherence

In this paper, we have attempted two ambitious tasks. We have undertaken a wide-ranging survey of the Network learning (NL) literature, and tried to identify the emerging themes of this work. We have selected three of these themes, and in each case tried to identify the main theoretical perspectives in use, the main directions of the studies, and the key ideas being addressed and researched. We have also tried to indicate where the main research effort might be directed in order to help to ‘fill in the gaps’ and achieve some coherence for the theme. Our second major task has arisen from our assertion that the field of Networked Learning research is theoretically fragmented. We have argued that this situation arises because Networked Learning research is a new field, and is drawing upon a wide range of theoretical perspectives. However, unless we can achieve some synthesis of these perspectives we may find it difficult to establish a coherent research programme in the field. We argue that one way of developing some coherence is to make theory and praxis interact explicitly, in other words, to ‘converse’ with each other in our research. By this we mean, to use theory to interrogate praxis, and use praxis to modify and develop theory, thus moving towards perspectives that are changing theory, modifying and improving it. As part of this argument, we have briefly surveyed the current level of Theory–Praxis Conversation, either explicit, or implicit, in the thematic research we have described. It is clear that some outstanding work is being done to make theory work, and to modify it in the light of research into praxis. However, it is also the case that much current Networked Learning research does not interrogate the theory that it uses to contextualise it. We see Theory–Praxis Conversation as a way of thinking explicitly about how we might make the work of interrogating theory in our research more explicit and systematic. In this way, our ‘Quest for Coherence’ may, we hope, help Networked Learning research to climb up to the higher ground, and give us a wider ranging view of learning in networked environments.     

Study persistence and academic achievement as a function of the type of competing tendencies

In order to understand and predict students’ achievement and persistence at learning activities, many contemporary motivational models consider how much students are motivated for their school work. However, students’ achievement and persistence might not only be affected by their amount of study motivation, but also by the motivation to engage in competing alternative activities, as suggested three decades ago by Atkinson and Birch in their “Dynamics of Action” (1970). Building on this line of theorizing, the present contribution indicates that it is not only instructive to consider the level of students’ motivation for these competing activities, but also the type of activities they engage in, that is leisure vs. working activities. Two studies demonstrated that whereas time spent on working activities is inversely related to study motivation, attitude, persistence and academic achievement, such relationships were not found for leisure time engagement. Spending some time on leisure time activities does not interfere with optimal learning.     

How do high school students solve probability problems? A mixed methods study on probabilistic reasoning

When studying a complex research phenomenon, a mixed methods design allows to answer a broader set of research questions and to tap into different aspects of this phenomenon, compared to a monomethod design. This paper reports on how a sequential equal status design (QUAN → QUAL) was used to examine students’ reasoning processes when solving probability problems. A select clustered sampling resulted in the inclusion of 168 high school students in a first, quantitative phase, in which a questionnaire was used to assess how they solved probability problems. This questionnaire included probability items that were based on the outcome orientation, the representativeness misconception, and the equiprobability bias. In a second, qualitative phase, 18 students who were purposefully sampled from the first research phase were interviewed in order to conduct an in-depth study of their probabilistic reasoning processes. In this paper, we illustrate and discuss how several mixed methods research purposes were realized throughout our study: development, expansion, and initiation.     

Continuing attachments in academic work in neoliberal times: on the academic mode of existence

Is there (still) something specific about academic practice in contemporary neoliberal times? This article reports on a sociomaterial, ethnographic study informed by Deleuze’s untimely empiricism conducted at two research centres of a research university. We unfold the specificity of ‘the academic’ by elaborating upon two central notions: relational aspirations (the attachments of these academics, and the operations that such attachments generate) and mode of existence (the way academic practice comes into being by and through these attachments). The article discerns four types of relations that are typical for academic practice and argues that the way in which academic practice exists nowadays is characterized by a continuous distancing in action, that is, by drawing things together and by slowing things down.     

The motivating role of positive feedback in sport and physical education: evidence for a motivational model

Based on self-determination theory (Deci & Ryan, 2000), an experimental study with middle school students participating in a physical education task and a correlational study with highly talented sport students investigated the motivating role of positive competence feedback on participants' well-being, performance, and intention to participate. In Study 1, structural equation modeling favored the hypothesized motivational model, in which, after controlling for pretask perceived competence and competence valuation, feedback positively predicted competence satisfaction, which in turn predicted higher levels of vitality and greater intentions to participate, through the mediation of autonomous motivation. No effects on performance were found. Study 2 further showed that autonomous motivation mediated the relation between competence satisfaction and well-being, whereas a motivation mediated the negative relation between competence satisfaction and ill-being and rated performance. The discussion focuses on the motivational role of competence feedback in sports and physical education settings.     

Development and validation of the goal content for exercise questionnaire

Self-determination theory (SDT; Deci & Ryan, 2000) proposes that intrinsic, relative to extrinsic, goal content is a critical predictor of the quality of an individual's behavior and psychological well-being. Through three studies, we developed and psychometrically tested a measure of intrinsic and extrinsic goal content in the exercise context: the Goal Content for Exercise Questionnaire (GCEQ). In adults, exploratory (N = 354; Study 1) and confirmatory factor analyses (N = 312; Study 2) supported a 20-item solution consisting of 5 lower order factors (i.e., social affiliation, health management, skill development, image and social recognition) that could be subsumed within a 2-factor higher order structure (i.e., intrinsic and extrinsic). Evidence for external validity, temporal stability, gender invariance, and internal consistency of the GCEQ was found. An independent sample (N = 475; Study 3) provided further support for the lower order structure of the GCEQ and some support for the higher order structure. The GCEQ was supported as a measure of exercise-based goal content, which may help understand how intrinsic and extrinsic goals can motivate exercise behavior.