Browsing while reading: effects of instructional design and learners' prior knowledge

One of the key reasons that multimedia, and particularly hypertext systems, are gaining in importance is that they inspire hopes of optimizing learners' processes of knowledge construction. The present study is concerned with the respective influence of individual learner variables (i.e. particularly domain‐specific prior knowledge) on the use of different design attributes. Thirty‐six university students worked through a hierarchically structured two‐part hypertext about the psychology of memory under two experimental browsing conditions (reduced versus free browsing). Results show that deeper‐level comprehension (i.e. structural knowledge) was predicted by the interaction of experimental condition and prior knowledge, but that simply retaining facts was not. Participants with low prior knowledge performed better on the comprehension test if they had worked on the version with reduced access. Moreover, the version with reduced access helped to reduce feelings of disorientation. The measure of disorientation also appeared to be closely linked with the individual's computer experience, self‐concept of computer ability and subject‐related interest. The main implications for educational practice relate to the design of an adaptive multimedia and hypertext learning system and the successful learning with it

The Generalized Internal/External Frame of Reference Model: An Extension to Dimensional Comparison Theory

The dimensional comparison theory (DCT) is based on the internal/external frame of reference model (I/E model). The model focuses on the effects of external (e.g., “How good am I in math compared to my classmates?”) and internal, dimensional comparisons (e.g., “How good am I in math compared to English?”) on academic self-concepts with widespread consequences for students’ self-evaluation, motivation, and behavioral choices. This article presents an extension to the DCT: The proposal of a generalized internal/external frame of reference model (GI/E model that allows the application of previous findings on academic self-concepts to a variety of domain-specific comparison targets and standards. On the side of targets and standards it not only deals with the academic area but also with other areas, which are compared intra-individually. On the side of the consequences, it deals with other variables besides self-concepts, i.e. with motivational constructs, (learning) behaviors or personality characteristics as the outcomes of external and dimensional comparison processes. The present article closes with an examination and discussion of the contributions of the DCT by applying standards of good theories to it

Synthesis of poly(vinyl ether)s with perfluoroalkyl pendant groups

2-Perfluoro(alkyl)ethyl vinyl ethers, F(CF2)nCH2CH2OCHCH2, (n = 6 or 8), were synthesized and polymerized by means of cationic initiators (HI/ZnI2 and CF3SO3H/(CH3)2S). The perfluorohexyl-substituted poly(vinyl ether) is completely amorphous. The polymer with perfluorooctyl segments shows side chain crystallization with a disordering transition. For the corresponding perfluorooctyl monomer a liquid-crystalline phase was observed before melting. Copolymerization experiments of the flurocarbon-segmented monomers with a vinyl ether containing a cyanobiphenyl group in the side chain did not give homogeneous copolymers. This is attributed to the slower rate of polymerization of the fluorinated vinyl ethers as compared with the liquid-crystalline comonomer

The Annual Peak in the SST Anomaly Spectrum

The manner in which monthly mean sea surface temperature anomalies (SSTAs) show enhanced variance at the annual period in the extratropics (an annual peak in the variance spectrum) is illustrated by observations and model simulations. A mechanism, related to the reemergence of winter SST anomalies, is proposed to explain the annual peak in SST spectrum. The idea is supported by the analysis of a hierarchy of models, including Intergovernmental Panel on Climate Change model simulations. The results of the model experiments further suggest that the annual peak is either weak or absent if decadal SST variability is forced by local air–sea interaction. However, if ocean subsurface temperature variability forces decadal SST variability, the annual peak is much stronger. Strong annual peaks may therefore be seen as an indication of ocean-forced decadal SST variability in the extratropics

Perceived teacher unfairness and student motivation in math and German. An application of the generalized internal/external frame of reference model

The Generalized Internal/External Frame of Reference Model offers a framework according to which the perception of teacher characteristics might impact on students\u27 motivation within and between subjects. In the present study, relations between perceived teacher unfairness and student motivation in math and German were examined. In a sample of N = 1685 German secondary school students, perceived teacher unfairness was found to be negatively related with student self-concept, interest, and importance of doing well on the task within the subjects of math and German, while being positively related with the three aspects of student motivation between subjects. Mediation analyses revealed partial mediation through academic self-concept within, and complete mediation between subjects. The results imply that students\u27 motivation in one subject is not only related to perceived teacher characteristics in the corresponding subject, but also to the experiences that these students make with teachers in another subject. (DIPF/Orig.

Nonfouling Surface Coatings Based on Poly(2-methyl-2-oxazoline)

Surface fouling, i.e. the non-specific surface adhesion of proteins, bacteria and higher organisms, poses a severe problem in many areas ranging from modern diagnostic and therapeutic medical devices to food processing and food wrapping technology to corrosion prevention and marine technology. One approach to address these problems is to coat surfaces with nonfouling polymers. The properties of a new class of nonfouling polymer coatings made from poly(2-methyl-2-oxazoline) (PMOXA) were investigated here in comparison with the most frequently used polymer in this context, poly(ethylene glycol) (PEG). Both polymers were side-chain grafted onto a polycationic poly-L-lysine (PLL) backbone. The PMOXA graft copolymers spontaneously self-assembled to form monolayers on negatively charged surfaces. PMOXA surface coatings were as efficient as PEG-based coatings in suppressing protein and bacterial adsorption. The minimal number of side chain monomer units per surface area that are needed to obtain fully resistant surfaces was lower though for PMOXA than for PEG graft copolymers as a result of the higher molecular weight of the PMOXA monomer unit

What Works in School? Expert and Novice Teachers’ Beliefs about School Effectiveness

In 2009, John Hattie first published his extensive metasynthesis concerning determinants of student achievement. It provides an answer to the question: “What works in school?” The present study examines how this question is answered by pre- and in-service teachers, how their beliefs correspond to the current state of research and whether they differ according to the teachers' level of expertise. Thus, it takes on a novel approach as it draws on data from two sources in the field of education -- empirical research and teachers’ beliefs -- and examines their similarities and differences. The teachers’ beliefs were elicited by asking N = 729 participants to estimate the effect sizes of several determinants of student achievement. Those were compared to the empirical effect sizes found by Hattie (2009). Profile correlations showed that expert teachers’ beliefs are more congruent with current research findings than those of novice teachers. We further examined where expert and novice teachers’ beliefs differ substantially from each other by using confirmatory factor analysis (CFA) and comparing group means in latent variables. Our findings suggest that teachers’ beliefs about school effectiveness are related to professional experience: Expert teachers showed a stronger overall congruence with empirical evidence, scoring higher in achievement-related variables and lower in variables concerning surface- and infrastructural conditions of schooling as well as student-internal factors. Results are discussed with regard to teacher-education practices that emphasize research findings and challenge existing beliefs of (prospective) teachers

Time-Periodic Solutions to the Equations of Magnetohydrodynamics with Background Magnetic Field

In the first part of this thesis we extend the theory of anisotropic Triebel-Lizorkin spaces to time-periodic functions. In particular, the spatial trace space is determined together with the existence of extension operators. Additionally, some results regarding pointwise multiplication are provided. As a preparation for this theory we prove a transference principle for multipliers with values in the spaces of summable sequences. Secondly, we consider the equations of magnetohydrodynamics with a background magnetic field and time-periodic forcing. Maximal regularity of the time-periodic linear problem is established by applying the results of the first part. The existence of a solution to the non-linear problem is shown for a large class of background magnetic fields via a fixed-point argument

Feedback on teachers' text assessment: Does it foster assessment accuracy and motivation?

Teachers' assessment of students' performance on complex tasks, such as writing, is important both for their teaching and for students' learning. Teachers must be able and motivated to assess texts correctly. According to theoretical assumptions, feedback can help promote the diagnostic competencies required to assess texts correctly, but, up until now, no empirical studies have examined the effects of accuracy feedback on teachers' assessments. We conducted an experimental study comparing the effects of two feedback interventions with a practice-only control group on teachers' assessment accuracy and motivation. Student teachers (n = 181) and experienced teachers (n = 114) assessed 10 students' texts in all groups. The feedback in both of the feedback groups showed the teachers a comparison between their own assessments and correct assessments. We varied the feedback presentation between one single presentation after five texts and single presentations after each of the first five texts. We measured assessment accuracy and situational interest, which conceptualizes motivation, to assess the next five texts. The results showed that feedback promoted situational interest but not assessment accuracy. We discuss why teachers found feedback interesting and under what circumstances training interventions could be useful.Die Beurteilungen von Lehrkräften zu den schriftlichen Leistungen ihrer Schülerinnen und Schüler spielen eine wichtige Rolle für die Unterrichtsgestaltung und das Lernen. Daher sollen für die Aus- und Weiterbildung von Lehrkräften Trainingsmöglichkeiten geschaffen werden, welche die Kompetenz und Motivation der Lehrkräfte zur korrekten Beurteilung erhöhen. Es ist anzunehmen, dass Feedback diagnostische Kompetenzen fördern kann, aber momentan fehlt es an empirischen Studien, die die Effektivität von Feedback im Vergleich zu Beurteilungsübungen ohne Feedback untersuchen. Der vorliegende Artikel stellt eine experimentelle Studie vor, in der die Effekte von zwei Feedback-Interventionen auf die Beurteilungsgenauigkeit und Motivation der Lehrkräfte mit einer Kontrollgruppe, in der Texte ohne Feedback beurteilt wurden, verglichen wurden. Lehramtsstudierende (n = 181) und erfahrene Lehrkräfte (n = 114) bewerteten in allen Gruppen zehn Schülertexte. In beiden Feedbackbedingungen wurde den Lehrkräften ein Vergleich der eigenen Bewertung mit der Bewertung des Textes durch Expert:innen gezeigt. Zwischen den Gruppen variierte die Feedback-Präsentation zwischen einer einmaligen Präsentation nach fünf Texten und mehrmaliger Präsentation nach jedem der ersten fünf Texte. Danach wurde die Motivation weitere Texte zu beurteilen, sowie die Beurteilungsgenauigkeit bei der Beurteilung der zweiten fünf Texte gemessen. Die Ergebnisse zeigten, dass beide Feedbackbedingungen im Vergleich zur Kontrollgruppe das situative Interesse an der Beurteilung förderten, aber nicht die Genauigkeit. Es wird diskutiert, warum Lehrkräfte die Beurteilung mit Feedback interessanter fanden und unter welchen Umständen Trainingsinterventionen nützlich sein können.Peer Reviewe

Throw Them All in One Pot? Differences in Stereotypes About Subgroups of Pre-Service Teachers

According to the stereotype content model, stereotypes can be described by using the dimensions competence and warmth. Compared to other professions, teaching is associated with a paternalistic stereotype consisting of high warmth and low competence. In four studies, stereotypes about different subgroups of pre-service teachers were compared. The aim was to understand sub-stereotypes better that could lead to different levels of stereotype threat and adverse behavioral tendencies. In Study 1 (N = 335), we compared stereotypes about elementary school pre-service teachers, grammar school pre-service teachers, computer science students, law students, and psychology students reported by pre-service teachers and psychology students. In contrast to nonteaching students, both groups of pre-service teachers corresponded to the paternalistic stereotype. In Study 2 (N = 243), pre-service teachers reported stereotypes about pre-service teachers for elementary schools, special education schools, comprehensive schools, vocational schools, and grammar schools. Elementary school pre-service teachers were stereotyped most paternalistically, while grammar school pre-service teachers matched the paternalistic stereotype the least. The ratings of other school types mostly fell between these extremes. In Studies 3a (N = 133, open-ended questions) and 3b (N = 308, closed-ended questions), students of various study programs compared pre-service teachers majoring in German and history (representing a non-STEM major combination) to pre-service teachers with the majors mathematics and physics (representing a STEM major combination). Pre-service teachers studying German and history were rated warmer but less competent than pre-service teachers with the majors mathematics and physics, confirmed by both methods of measuring stereotypes. In Studies 1, 3a, and 3b, ingroup favoritism in the ratings by pre-service teacher participants was tested and only found for competence in Study 1. The importance of our results and their implications for stereotype threat effects and possible interventions are discussed