Measuring Search Engine Quality

The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures.     

What Teachers Take from Professional Development: Cases and Implications

In this article, we report on an 18-month longmathematics professional development projectwith elementary school teachers. Using a modelwe developed, three participant case studieswere analyzed with respect to not only theprofessional development milieu, but also howthese teachers interacted with the professionaldevelopment experience. In particular we foundthat having teachers reflect on new, authenticreform-oriented mathematics learningexperiences leads some teachers to take aninquiry stance concerning their own teaching,resulting in self-sustaining changes in theirmathematics instructional practices. Thisimplies that professional development forelementary mathematics teachers should includechallenging mathematics learning experiencescomplete with opportunities to reflect on personal and professional implications.     

The Role of Study Habits in Foreign Language Courses

The purpose of this study was to determine which study habits distinguish successful from unsuccessful foreign language learners. Participants were 219 college students from a variety of disciplinary backgrounds, enrolled in either Spanish, French, German or Japanese classes. A canonical discriminant analysis (F [6, 117], p < 0.0001; canonical R = 0.92) revealed that, compared to their high-performing counterparts, students with the lowest levels of foreign language performance tended to report that: (a) they frequently include a lot of irrelevant or unimportant information in their notes; (b) when they have difficulty with their assignments, they do not seek help from their instructor; (c) they put their lecture notes away after taking the test and never consult them again; (d) they have to be in the mood before attempting to study; (e) they have a tendency to doodle or to daydream when they are trying to study; and (f) they do not look up in a dictionary the meanings of words that they do not understand. Implications are discussed.     

Peer relations across contexts: individual-network homophily and network inclusion in and after school

Peer relations across 2 contexts (in school and after school) were examined for 577 participants, approximately 12 years old, from 3 middle schools in Milan, Italy. The primary research questions were: Do peer networks from different contexts uniquely contribute to explaining variance in individual behavior? Do measures of peer preference and peer network inclusion across contexts uniquely contribute to explaining individual depressive symptoms? Structural equation models showed that both the in-school and the after-school peer networks uniquely contributed to explaining variance in 2 types of individual problem behavior (in-school problem behavior, after-school delinquency), and that similarity with the 2 peer networks varied according to behaviors specific to each context and across gender. Finally, both in-school and after-school peer network inclusion contributed to explaining variance in depressive symptoms, after controlling for classroom peer preference.