Query processing in a retrospective document retrieval system that uses word fragments as language elements

The structure of a retrospective information retrieval system that uses equifrequent word or text fragments is described, and its advantages over word oriented systems are mentioned briefly. Word fragments are proposed as retrieval elements, and a discussion is given of the changes required in order to process a query. Some necessary modifications in the treatment of logical operators are described, and two conditions are postulated as necessary for the successful operation of the system. Aspects of query processing are illustrated by experimental results obtained from single and two-term queries applied to a portion of the MARC tapes.     

On orthogonal polynomials

A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown.     

Tackling Suboptimal Bachelor��s Degree Completion Rates Through Training in Self-Regulated Learning (SRL)

In response to both problematic and extant gaps in Bachelor??s degree completion rates, this mixed methods study investigated whether a theoretically based undergraduate course intervention measurably contributed to participants?? competence as self-regulated learners. Respective quantitative and qualitative analyses of data collected from two samples showed that intervention participants experienced growth in the targeted self-regulatory constructs. Moreover, differential effects by race/ethnicity and gender were not observed. We conclude with a discussion of this study??s implications for institutions of higher education, pertinent considerations in designing and implementing this self-regulated learning intervention, and a review of the literature on effective practices for doing so.     

Contexts of reading instruction: Implications for literacy skills and kindergarteners’ behavioral engagement

This observational study examined kindergarteners’ (n = 170) exposure to literacy instruction in their classrooms (n = 36), child-by-instruction interactions, and behavioral engagement in relation to literacy skills. Time spent in four instructional contexts was coded according to who managed children's attention (teacher-managed, TM or child-managed, CM), and the content focus (basic skills such as teaching letters and their sounds, or meaning-focused such as discussing a book); children's behavioral engagement and off-task behavior were also coded live five times over the year. Word-reading and phonological awareness skills were assessed in fall and spring. Hierarchical Linear Modeling results indicated that kindergarteners with lower initial skills gained more in word-reading, but not phonological awareness, when they were exposed to relatively more time in TM basic skills instruction. In contrast, more time in CM meaning-focused instruction did not interact with initial skills to predict either outcome. Engagement analyses indicated that students were more likely to be off-task in CM than in TM contexts. Children who spent more time off-task during TM contexts had lower spring scores on both outcomes. Discussion explores the implications of this work for both literacy learning and behavioral engagement in the transition year of kindergarten.     

Developing children's conceptual understanding of area measurement: A curriculum and teaching experiment

The present study examined the effectiveness of three instructional treatments which had different combinations of mathematical elements regarding 2-dimensional (2-D) geometry and area measurement for developing 4th-grade children's understanding of the formulas for area measurement and their ability to solve area measurement problems. Participants were 120 fourth graders. The results showed that the enriched curriculum, involving the geometry motions and area measurement connections effectively facilitated children's mathematical judgments and explanations demanding high-level conceptual understanding. The instructional curricula accentuating only 2-D geometry or numerical calculations for area measurement did not exhibit such effectiveness. Interview data revealed that the geometric operations of superimposition, decomposition, re-composition as well as the concept of congruence were deemed essential by children for the conceptualization of the formulas for area measurement.     

Motivation and students’ use of learning strategies: Evidence of unidirectional effects in mathematics classrooms

Considerable evidence indicates that student motivation and use of learning strategies are related. There is insufficient understanding, however, about their reciprocal effects—whether motivation affects strategy use, the converse, or whether the effects are bidirectional—and which components of motivation and strategies are involved. A two-wave longitudinal design was used to examine this issue among 9th grade students (N = 306) enrolled in high school mathematics classes during an academic term. A cross-lagged structural model found that students’ self-efficacy in mathematics and value predicted their reported use of learning strategies. There was no evidence, however, that learning strategy use predicted motivation and, thus, support for unidirectional effect of motivation during that time interval. Implications for models of self-regulated learning and instruction are discussed.     

Academic delay of gratification and children's study time allocation as a function of proximity to consequential academic goals

Students (N = 302) in Chinese elementary schools were assessed regarding their academic delay of gratification (ADOG) and reported the time they devoted to non-school study and playtime during an extended interval prior to taking a high-stakes final exam. Students high compared those low in ADOG were more likely to spend time studying and less time playing several weeks prior to the exam. Growth curve analyses verified, however, that this difference diminished as a function of the temporal proximity to the exam, and that the group differences were non-existent just before the exam. Associations between ADOG and students' academic motivation and use of learning strategies replicated those obtained previously with adults in the USA. Results contribute to the general literatures on volition, homework and the dynamics of conflicting goals and action tendencies.     

Classroom and technology-supported help seeking: The need for converging research paradigms

Contributions to this special section represent advances in understanding help seeking as a self-regulated learning strategy that occurs in classrooms, during computer-mediated communications, and when using intelligent systems that provide help to improve learners’ help-seeking skills and knowledge acquisition. Collectively, the research and development contributes information relevant for all phases of the help-seeking process. My comments focus on: (a) features of technology-supported help seeking that have implications for motivation, (b) the need for increased attention to the instructional context in which technology-supported help seeking occurs, (c) a necessary convergence of classroom and technology-supported help-seeking research paradigms, and (d) reconsideration of help seeking as a social-interactive strategy.     

Epistemic states and traits: preschoolers appreciate the differential informativeness of situation-specific and person-specific cues to knowledge

Previous research has demonstrated that preschoolers can use situation-specific (e.g., visual access) and person-specific (e.g., prior accuracy) cues to infer what others know. The present studies investigated whether 4- and 5-year-olds appreciate the differential informativeness of these types of cues. In Experiment 1 (N = 50), children used others' prior labeling accuracy as a cue when learning labels for, but not the visual identity of, hidden objects. In Experiment 2 (N = 64), with both cues present, children attended more to visual access than prior accuracy when learning the visual identity of, but not labels for, hidden objects. These findings demonstrate that children appreciate the difference between situation- and person-specific cues and flexibly evaluate these cues depending on what information they are seeking.