Management and Conflation of Multiple Representations within an Open Federation Platform

Building up spatial data infrastructures involves the task of dealing with heterogeneous data sources which often bear inconsistencies and contradictions, respectively. One main reason for those inconsistencies emerges from the fact that one and the same real world phenomenon is often stored in multiple representations within different databases. It is the special goal of this paper to describe how the problems arising from multiple representations can be dealt with in spatial data infrastructures, especially focusing on the concepts that have been developed within the Nexus project of the University of Stuttgart that is implementing an open, federated infrastructure for context-aware applications. A main part of this contribution consists of explaining the efforts which have been conducted in order to solve the conflicts that occur between multiple representations within conflation or merging processes to achieve consolidated views on the underlying data for the applications

Technologies to Enhance and Extend Children\u27s Understanding of Geometry: A Configurative Thematic Synthesis of the Literature

Empirical evidence indicates that students are not learning geometry with relational understanding of the concepts. Studies have shown that digital technologies can support students in mathematics. The purpose of this study was to find which technologies and technological affordances are specific to learners of geometry. This paper presents the results of a configurative thematic synthesis of empirical studies and theoretical papers to show that dynamic geometry environments (DGEs: including 3D DGEs) and logobased environments were the main types of technologies used to support geometry learners. The results of this study also reveal that there are five main technological supports provided to geometry learners - visualization, manipulation, cognitive tools, discourse promoters, and ways of thinking

Individual differences in proof structures following multimodal logic teaching

We have been studying how students respond to multimodal logic teaching with Hyperproof. Performance measures have already indicated that students' pre-existing cognitive styles have a significant impact on teaching outcome. Furthermore, a substantial corpus of proofs has been gathered via automatic logging of proof development. We report results from analyses of final proof structure, exploiting (i) `proofograms', a novel method of proof visualisation, and (ii) corpus-linguistic bigram analysis of rule use. Results suggest that students' cognitive styles do indeed influence the structure of their logical discourse, and that the effect may be attributable to the relative skill with which students manipulate graphical abstractions. Introduction: multimodal logical discourse Computer-based multimodal tools are giving people the freedom to express themselves in brand new ways. But what do people actually do when given these tools? Does everyone end up generating the same form..

Validierung der deutschen Übersetzung der Centrality of Event Scale (CES-G)

Theoretischer Hintergrund: Eine wachsende Zahl von Forschungsarbeiten weist auf die Bedeutung der wahrgenommenen Zentralität eines traumatischen Ereignisses in der eigenen Lebensgeschichte für das Verständnis von Symptomen der Posttraumatischen Belastungsstörung (PTBS) hin. Zur Untersuchung dieser Beziehung exisitert bislang noch kein Messinstrument, das die Ereigniszentralität auf Deutsch erfasst. Fragestellung: Um die Forschung auf diesem Gebiet im deutschsprachigen Raum zu ermöglichen, wird die Centrality of Event Scale (CES; Berntsen & Rubin, 2006) in einer deutschen Übersetzung (CES-G) vorgestellt und hinsichtlich ihrer psychometrischen Eigenschaften untersucht. Methode: Zur psychometrischen Auswertung wurde die CES-G 322 Student_innen sowie 115 ambulanten Patient_innen mit ausgeprägter PTBS-Symptomatik vorgelegt. Ergebnisse: Die CES-G zeigt eine hervorragende interne Konsistenz, substanzielle Korrelationen mit Maßen von PTBS Symptomen, allgemeiner Psychopathologie, Depressivität und maladaptiven kognitiven Prozessen sowie eine kriterienbezogene Validität bezüglich PTBS Symptomen in einer klinischen Stichprobe. Schlussfolgerungen: Die deutsche Übersetzung der CES ist ein verlässliches und valides Messinstrument für Ereigniszentralität.Background: A growing body of research points to the importance of the perceived centrality of a traumatic event in one′s life story for understanding posttraumatic stress disorder (PTSD) symptoms. To date, no instrument measuring event centrality is available in German to examine this relationship. Objective: To enable research in the German-speaking countries on the Centrality of Event Scale (CES; Berntsen & Rubin, 2006), a German translation (CES-G) is introduced and examined for its psychometric properties. Methods: For the psychometric evaluation, the CES-G was presented to 322 undergraduates and 115 psychiatric outpatients with substantial PTSD symptomatology. Results: The CES-G shows excellent internal consistency, substantial correlations with measures of PTSD symptoms, psychopathology, depression, and maladaptive cognitive processes as well as criteria-related validity regarding PTSD symptoms in a clinical sample. Conclusions: The German translation of the CES is a reliable and valid measure for event centrality

From dual coding to multiple coding : Effects of multiple symbolic representations for mathematical understanding

Multiple representations are fundamental elements of learning materials. Following Seufert (2003), the term multiple representations refers to the combination of two or more representations, containing the same or differing content and consisting of the same or differing modality and codality. In multimedia research, usually the effectiveness of combining representations of different types of codality (mostly text and image) is examined, showing to be more effective for learning when presented together than when presented alone (multimedia effect, for example, Mayer, 2009). There are plausible theoretical models for effects of these combinations, usually assuming two different channels at least for the initial processing of the information from multiple representations (for example, Paivio, 1986; Schnotz & Bannert, 1999, 2003). In mathematics and science education, multiple symbolic representations are combined as well. These combinations differ from the previously mentioned text-picture combinations in so far as they do not contain both a symbolic and an analogously coded representation, but two symbolically coded representations. However, these are encoded in different character systems, such as, for example, text and formula. Comparably rarely, these combinations are examined in the research on multiple representations, and no hypotheses on differentiation between representations of the same code but different coding systems can be derived from the available theoretical models. The present thesis investigates how learners deal with multiple symbolic representations. In several multirepresentational experiments, two questions are examined: first, whether the principles of multimedia learning can be applied to multiple symbolic representations, and second, based on the results of these studies, whether the common theories on multimedia learning must be differentiated with regard to multiple symbolic representations. Focusing on the investigation of multiple symbolic representations, the first study was conducted in order to search for empirical evidence of differing influence of text and formulas on performance and to test material from the mathematical field of elementary propositional logic. Results reveal differences between the use of text and formulas and the significant influence of the direction of representational change between the two forms of representation on performance, where formulas stand out as the more difficult representation. These results lead to the question of whether this difference is large enough to replicate the multimedia effect for multiple symbolic representations. Therefore, in the second study, the multimedia effect was investigated using materials specifically designed to precisely separate the two relevant factors of quantity and diversity of representations possibly causing this effect. Quantity here means the number of representations given, whereas diversity stands for whether or not the used representations differ in their coding. Results of study 2 deliver for the first time empirical evidence for the multimedia effect based on multiple symbolic representations, which is comparable in its large effect size to results based on symbolic and analog representations. On the basis of studies 1 and 2, the third and final study examines the question whether, in addition to the multimedia effect, further principles of multimedia learning such as the generation principle for multiple symbolic representations can be replicated. Therefore, the third study investigated whether previous generation of the missing representation leads to better performance. In line with the first study, results of study 3 confirm the difficulties with the formula representation showing that generating formulas is more difficult than generating text. Additionally, results provide evidence for a multimedia effect based on multiple symbolic representations when presented simultaneously. By investigating the special case of symbolic mathematical representations within the setting of multimedia learning theories, the results of this thesis contribute to research in three major ways: First, by using the example of elementary propositional logic, the results provide evidence for the fostering effect of multiple symbolic representations (text and formula), especially when presented in combination. Second, this thesis shows that the principles of multimedia learning cannot be transferred directly to the special case of multiple symbolic representations, which is for example the case for learner-generated representations. Thirdly and as the main finding, the presented work provides the replication of the multimedia effect for multiple symbolic representations, which will add to the further development of cognitive theories and positively impact the design of multirepresentational learning in STEM education.Multiple Repräsentationen gelten als grundlegende Elemente von Lernmaterialien. Der Begriff multiple Repräsentationen meint die „Kombination von mindestens zwei Repräsentationen gleichen oder unterschiedlichen Inhalts, sowie gleicher oder unterschiedlicher Kodalität und Modalität“ (Seufert, 2003, S. 11). In der Multimediaforschung wird zumeist die Wirksamkeit der Kombination von Repräsentationen unterschiedlicher Kodalität untersucht (meistens Text und Bild), die zusammen präsentiert lernförderlicher sind als eine Repräsentation alleine (Multimedia-Effekt, z.B. Mayer, 2009). Für die Wirkung dieser Kombinationen liegen plausible theoretische Modelle vor, die in der Regel von verschiedenen Kanälen zumindest für die anfängliche Verarbeitung der Informationen aus multiplen Repräsentationen ausgehen (z.B. Paivio, 1986; Schnotz & Bannert, 1999, 2003). Vor allem im mathematischen und naturwissenschaftlichen Unterricht werden jedoch häufig auch multiple symbolische Repräsentationen kombiniert, die allerdings in unterschiedlichen Zeichensystemen kodiert sind, wie z.B. Text und Formel. Vergleichsweise selten werden diese Kombinationen in der Forschung zu multiplen Repräsentationen untersucht und aus den vorliegenden theoretischen Modellen lassen sich hierzu keine Hypothesen zur Differenzierung zwischen Repräsentationen ableiten, die zwar von gleicher Kodalität sind, aber aus unterschiedlichen Kodierungssystemen stammen. In der vorliegenden Arbeit geht es daher um den Umgang von Lernenden mit multiplen symbolischen Repräsentationen. In mehreren Experimenten zu multiplen Repräsentationen werden zwei Fragestellungen untersucht: zum einen, ob sich die Prinzipien multimedialen Lernens auf multiple symbolische Repräsentationen übertragen lassen und zum anderen, ob ausgehend von diesen Ergebnissen gängige Theorien zum Lernen mit Multimedia hinsichtlich multipler symbolischer Repräsentationen differenziert werden müssen. Um multiple symbolische Repräsentationen zu untersuchen, wurde die erste Studie durchgeführt, wobei nach empirischen Belegen für den unterschiedlichem Einfluss von Text und Formeln auf die Leistung gesucht und Material aus dem mathematischen Feld der elementaren propositionalen Logik getestet wurde. Die Ergebnisse zeigen Unterschiede in der Verwendung von Text und Formeln und den signifikanten Einfluss der Richtung des Repräsentationswechsels zwischen den beiden Darstellungsformen auf die Leistung, wobei Formeln sich als die schwierigere Darstellung herausstellen. Diese Ergebnisse führen zu der Frage, ob dieser Unterschied groß genug ist, um den Multimediaeffekt für multiple symbolische Repräsentationen replizieren zu können. Daher wurde in der zweiten Studie der Multimedia-Effekt unter Verwendung eigens konzipierter Materialien untersucht, um die relevanten Faktoren Quantität und Diversität von Repräsentationen, die diesen Effekt möglicherweise bewirken, präzise zu trennen. Quantität steht hier für die Anzahl der gegebenen Repräsentationen, während Diversität bedeutet, ob sich die verwendeten Repräsentationen in ihrer Kodierung unterscheiden oder nicht. Die Ergebnisse aus Studie 2 liefern zum ersten Mal empirische Evidenz für den Multimedia-Effekt auf der Basis multipler symbolischer Repräsentationen, wobei die hohen Effektstärken vergleichbar sind mit Ergebnissen, die auf symbolischen und analogen Repräsentationen basieren. Auf der Grundlage von Studie 1 und 2 wird in der dritten und letzten Studie der Frage nachgegangen, ob sich neben dem Multimediaeffekt auch weiterführende Prinzipien multimedialen Lernens wie das Generierungsprinzip für multiple symbolische Repräsentationen replizieren lässt. Darum wird nun in der dritten Studie detailliert untersucht, ob die vorherige Generierung der fehlenden Darstellung zu einer besseren Leistung führt. In Übereinstimmung mit der ersten Studie bestätigen die Ergebnisse der dritten Studie die Schwierigkeiten mit der Formelrepräsentation hinsichtlich dessen, dass die Generierung von Formeln deutlich schwerer ist als die Generierung von Text. Es finden sich außerdem Hinweise auf einen Multimedia-Effekt für multiple symbolische Repräsentationen, wenn sie gleichzeitig präsentiert werden. Aufgrund der Untersuchung des Spezialfalls symbolischer Repräsentationen im Rahmen multimedialer Lerntheorien, erweitern die Ergebnisse dieser Arbeit bisherige Forschung in dreierlei Hinsicht: erstens, indem am Beispiel der elementaren Aussagenlogik empirische Evidenz für die fördernde Wirkung multipler symbolischer Repräsentationen (Text und Formel) präsentiert werden kann, besonders für den Fall, wenn sie in Kombination eingesetzt werden; zweitens zeigen die Ergebnisse, dass die Prinzipien des multimedialen Lernens nicht eins zu eins auf den Sonderfall vielfacher symbolischer Repräsentationen übertragen werden, was beispielsweise bei selbst generierten Repräsentationen der Fall ist; und drittens liefert die vorgestellte Arbeit als wichtigstes Ergebnis die Replikation des Multimedia-Effekts für multiple symbolische Darstellungen - ein Ergebnis, das zur Weiterentwicklung kognitiver Theorien beitragen und die Gestaltung des Lernens mit multiplen Repräsentationen in der STEM-Ausbildung positiv beeinflussen wird

Trauma-Related Voices: Understanding Mechanisms of Maintenance and Change

Following a systematic review of the literature, a novel theory was developed to explain the relationship between trauma and hearing voices. The theoretical model was tested using cross-sectional, prospective, and qualitative research methods with clinical and non-clinical samples. This thesis concludes with a comprehensive research agenda to guide future research that may lead to the development of more effective treatments for trauma-affected voice hearers

AN EXAMINATION OF THE ROLE OF TECHNOLOGICAL TOOLS IN RELATION TO THE COGNITIVE DEMAND OF MATHEMATICAL TASKS IN SECONDARY CLASSROOMS

This study investigates the role of digital cognitive technologies in supporting students' mathematical thinking while engaging with instructional tasks. Specifically, the study sought to better understand how the use of technology is related to the cognitive demand of tasks. Data were collected in four secondary mathematics classrooms via classroom observations, collection of student work, and post-lesson teacher interviews. Opportunities for high level thinking by students were evaluated using the Mathematical Tasks Framework (Stein, Smith, Henningsen, & Silver, 2009). Technology use was evaluated with respect to whether it served to amplify students' thinking by making students' work more efficient or accurate without changing the nature of the task, or whether it was used to reorganize students' thinking by supporting a shift to something different or beyond what the technology was doing for them (Pea, 1985). Results indicate that the mere inclusion of technology in a task was not related to the cognitive demand during any of the three phases of implementation, as technology was used in both high and low level tasks. However, results suggested an association between the level of cognitive demand of a task and the way that technology was used. In general, when technology was used as an amplifier, it was not related to the thinking requirements of the task, while the use of technology as a reorganizer was central to the thinking requirements of the task. The decline of tasks set up at high level often corresponded to technology being used as an amplifier and reorganizer during set up, but as only an amplifier during implementation. Overall, the role of technology in the decline or maintenance of high level thinking during implementation seems to depend more on teachers' classroom practice than any particular issues related to the use of technology. How prepared students were to engage in high level thinking tasks in general, how teachers anticipated students' needs while using technology to engage with the task, and how teachers responded to student questions and difficulties were influential factors in the maintenance or decline of these tasks

THE EFFECT OF USING DRAGONBOX ON THE MATHEMATICS TEACHING EFFICACY OF PRESERVICE MIDDLE GRADE TEACHER

The purpose of this study was to examine the effects of using the mathematical simulation games of DragonBox on preservice middle-level teachers’ mathematics teaching efficacy. The study employed an embedded, exploratory case study design using mixed methods techniques. The study comprised of 33 preservice middle-level mathematics teachers enrolled in a course designed to prepare middle childhood educators to teach mathematics in urban, suburban or culturally diverse middle school classrooms. The purpose of the course was also to provide current and future middle school teachers with the mathematics content, essential concepts, methodology, activities, and resources to both learn and teach mathematics in grades 4-8. Quantitative and Qualitative data were collected using five instruments: Mathematics Teaching Self-Efficacy Scale (MTSES) (Ryang, 2010), researcher’s journal, observation logs, interview protocols and artifacts. Quantitative data analysis was conducted using Wilcoxon Signed-Rank nonparametric test and reliability measure. The qualitative data were analyzed using Lichtman’s (2013) six-step coding protocol through Dedoose’s (2017) web application. The units of analysis for the qualitative data consisted of episodes where the preservice mathematics teachers engage with DragonBox gaming environment. Results of the Wilcoxon Signed-Rank test showed no statistical significance (at p =.216) in the MTSES posttest median score compared to the MTSES pretest median score, which indicated no change in the level of mathematics teaching efficacy. Six themes emerged as a result of qualitative data analysis related to teacher perceptions and factors associated with teaching middle-level mathematics using DragonBox. The data gathered was triangulated from the qualitative data. Through the themes, participants indicated they perceived the use of DragonBox as a learning tool, differentiate way to engage future students, and goal-directed learning tool that still relied heavily on teacher support. Participants also expressed that conceptual understandings and careful planning were needed to connect with a highly technology-driven society. The themes that transpired from the triangulation of qualitative data and the quantitative data was reviewed through the lens of the causal model of triadic reciprocal causation. Overall, this study showed that upon engaging with DragonBox gaming environment, preservice teachers had a more positive perception of the usefulness of DragonBox in teaching middle-level mathematics

Using technology to facilitate visualization in multivariable calculus.

A multiyear study was undertaken to examine the effects of the use of a computer algebra system (Mathematica) on student learning in multivariable calculus at the University of Oklahoma. The research was both quantitative and qualitative, including pre- and post-questionnaires administered to 585 students over four semesters as well as task-based interviews. Although in early iterations of the data collection there were some apparent effects on spatial visualization skills, with the full data set it became apparent that these differences were artifacts of student self-selection into the "experimental" and "control" sections. In particular, gender and major course of study were responsible for considerable differences in visualization performance