Aufbau und Realisierung des MeDoc-Volltextspeichers

Zusammenfassung.   Ziel von MeDoc war der Aufbau eines verteilten Informationsdienstes, über den eine kritische Masse an Informatik-Literatur im Volltext nachgewiesen, langfristig vorgehalten, recherchiert und beschafft werden kann. Bei einem Teil der angebotenen Literatur handelt es sich dabei um elektronische Versionen des regul?ren kommerziellen Angebots der beteiligten Verlage. Aus diesem Grund war ein wichtiges Teilziel von MeDoc die Entwicklung eines Volltextspeichers, der solche kostenpflichtigen Dokumente abrechenbar und sicher nachweist, liefert und zum Browsen zur Verfügung stellt. Der Artikel beschreibt die Konzeption und Architektur dieses Volltextspeichers. Eingegangen am 17. April 1998 / Angenommen am 21. Juli 1998     

The relationship of interest to internal and external motivation

This study was conducted to examine the relationship between student interest and motivation. Previous studies have shown that measures of interest have attained positive relationships with global measures of motivation (Frymier, Shulman & Houser, 1996; Weber & Patterson, 2000). Additionally, even though a number of instructional researchers have speculated that interest is related to motivation through intrinsic means (Brophy, 1983; Mitchell, 1993; Schiefele, 1991; Schraw, Brunning & Svoboda, 1995; Stipiek, 1996; Tobias, 1994), there has been no systematic effort to provide any empirical evidence to these claims. Results indicate that interest is significantly related to intrinsic, but not extrinsic, motivation.     

Professional learning between past experience and future work

This paper deals with the professionalization of human service work. It analyses learning processes and identity development in the emerging profession of child care with concrete examples from empirical research, based on a life history approach. It discusses examples of careers mainly based on students’ life experience, pointing out that their immediate success in the workplace may inhibit an even better qualification they had been spurred to critical reflection. It further follows a sample of students through their theoretical education and trainee periods, illuminating their changing identification with and understanding of their future work, and their learning of professional knowledge and competences. The conclusion is that the new 3.5 year education in child care pedagogy clearly improves the professional competences of child care, but it also identifies a set of further specific challenges to be met for the development of real professional competences.     

Output-sensitive autocompletion search

We consider the following autocompletion search scenario: imagine a user of a search engine typing a query; then with every keystroke display those completions of the last query word that would lead to the best hits, and also display the best such hits. The following problem is at the core of this feature: for a fixed document collection, given a set D of documents, and an alphabetical range W of words, compute the set of all word-in-document pairs (w, d) from the collection such that w ∈ W and d ∈ D. We present a new data structure with the help of which such autocompletion queries can be processed, on the average, in time linear in the input plus output size, independent of the size of the underlying document collection. At the same time, our data structure uses no more space than an inverted index. Actual query processing times on a large test collection correlate almost perfectly with our theoretical bound.

Student difficulty in constructing proofs: The need for strategic knowledge

The ability to construct proofs is an important skill for all mathematicians. Despite its importance, students have great difficulty with this task. In this paper, I first demonstrate that undergraduates often are aware of and able to apply the facts required to prove a statement but still fail to prove it. They thus fail to construct a proof because they could not use the syntactic knowledge that they had. By comparing doctoral students and undergraduates constructing proofs in abstract algebra, I have hypothesized four types of `strategic knowledge' – knowledge of how to choose which facts and theorems to apply – which the doctoral students appeared to possess and undergraduates did not. The doctoral students appeared to know the powerful proof techniques in abstract algebra, which theorems are most important, when particular facts and theorems are likely to be useful, and when one should or should not try and prove theorems using symbol manipulation. This revised version was published online in July 2006 with corrections to the Cover Date.