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Tuomo Korenius Jorma Laurikkala Martti Juhola Kalervo Järvelin 《Information Retrieval》2006,9(1):33-53
Search facilitated with agglomerative hierarchical clustering methods was studied in a collection of Finnish newspaper articles
(N = 53,893). To allow quick experiments, clustering was applied to a sample (N = 5,000) that was reduced with principal components analysis. The dendrograms were heuristically cut to find an optimal partition,
whose clusters were compared with each of the 30 queries to retrieve the best-matching cluster. The four-level relevance assessment
was collapsed into a binary one by (A) considering all the relevant and (B) only the highly relevant documents relevant, respectively.
Single linkage (SL) was the worst method. It created many tiny clusters, and, consequently, searches enabled with it had high
precision and low recall. The complete linkage (CL), average linkage (AL), and Ward's methods (WM) returned reasonably-sized
clusters typically of 18–32 documents. Their recall (A: 27–52%, B: 50–82%) and precision (A: 83–90%, B: 18–21%) was higher
than and comparable to those of the SL clusters, respectively. The AL and WM clustering had 1–8% better effectiveness than
nearest neighbor searching (NN), and SL and CL were 1–9% less efficient that NN. However, the differences were statistically
insignificant. When evaluated with the liberal assessment A, the results suggest that the AL and WM clustering offer better
retrieval ability than NN. Assessment B renders the AL and WM clustering better than NN, when recall is considered more important
than precision. The results imply that collections in the highly inflectional and agglutinative languages, such as Finnish,
may be clustered as the collections in English, provided that documents are appropriately preprocessed. 相似文献
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Tuomo Erkki Virtanen Marja-Kristiina Lerkkanen Anna-Maija Poikkeus Matti Kuorelahti 《教育心理学》2015,35(8):963-983
Student engagement has been identified as an influential mediator between classroom interactional quality and adolescent learning outcomes. This study examined the relationship between classroom quality and student behavioural engagement in secondary school classrooms. Three dimensions of classroom quality (emotional, organisational and instructional support) and the dimension of student engagement were observed in nine classrooms using the Classroom Assessment Scoring System. Self-ratings of behavioural engagement were provided by 181 Finnish secondary school students along with their teachers’ ratings of classroom-level student engagement. The results showed, first, that there was variation in both classroom quality and student behavioural engagement between the classrooms. Second, classroom organisational support was associated with observed and with teacher- and student-rated engagement, and instructional support was associated with student-rated and observed engagement. Third, emotional support did not have a direct effect on student engagement but contributed to student engagement indirectly via organisational and instructional support. There were no gender differences with respect to self-reported engagement. Class size had a positive effect on teacher-rated engagement. The results demonstrated specific associations between the domains of classroom quality and student behavioural engagement in secondary school classrooms. 相似文献
4.
Eeva Eskola Eeva-Leena Kataja Jukka Hyönä Tuomo Häikiö Juho Pelto Hasse Karlsson Linnea Karlsson Riikka Korja 《Child development》2021,92(4):1539-1553
To investigate the role of early regulatory problems (RP), such as problems in feeding, sleeping, and calming down during later development, the association between parent-reported RP at 3 months (no-RP, n = 110; RP, n = 66) and attention to emotional faces at 8 months was studied. Eight-month-old infants had a strong tendency to look at faces and to specifically fearful faces, and the individual variance in this tendency was assessed with eye tracking using a face-distractor paradigm. The early RPs were related to a lower attention bias to fearful faces compared to happy and neutral faces after controlling for temperamental negative affectivity. This suggests that early RPs are related to the processing of emotional information later during infancy. 相似文献
5.
Niina Lintu Tuomo Tompuri Anna Viitasalo Sonja Soininen Tomi Laitinen Kai Savonen 《Journal of sports sciences》2013,31(7):652-659
AbstractWe investigated cardiovascular fitness and haemodynamic responses to maximal cycle ergometer exercise test in children. The participants were a population sample of 425 children (204 girls, 221 boys) aged 6–8 years. Heart rate (HR) and systolic blood pressure (SBP) were measured from the beginning of pre-exercise rest to the end of recovery period. We provided reference values for peak workload and changes in HR and SBP during and after maximal exercise test in girls and boys. Girls had a lower cardiovascular fitness, indicated by peak workload per body weight [mean (2 s) 2.7 (0.9) vs. 3.1 (1.0) W · kg–1, P < 0.001] and lean mass [mean (2 s) 3.5 (0.9) vs. 3.8 (1.0) W· kg–1, P < 0.001] than boys. Plateau or decline in SBP close to the end of the test was found in about third of children and was considered a normal SBP response. Girls had a slower HR decrease within 2 min after the test than boys [mean (2 s) 53 (18) vs. 59 (22) beats · min–1, P < 0.001]. The results are useful for physicians and exercise physiologists to evaluate cardiovascular fitness and haemodynamic responses to exercise in children and to detect children with low exercise tolerance or abnormal haemodynamic responses to exercise. 相似文献
6.
Katriina Schrey-Niemenmaa Tuomo Rintamaki Pertti Tormala 《European Journal of Engineering Education》2003,28(2):161-167
In this paper the authors will describe the concept of educational industry as the heart of a learning city in the context of the Espoo case. The different players and their roles will be discussed as well as the possible business logics of this expanding sector of industry. The preliminary plans are to situate living facilities in the modern learning city for people of all ages, fulfilling the concept of lifelong learning. From nursery schools up to university units as well as spare-time activities, from culture to sports and different clubs to outdoor recreation areas, there are possibilities for working via IT connections from home or in the enterprises around and having innovative surroundings for meeting different people and networking. Transportation for people and data to other parts of the capital and to the globe is also essential. The heart of the city will be the educational industry unit, a development and test place for educational products and a one-hatch portal for keeping up one's knowledge throughout one's life. The portal will consist of services from analysing the needs of the customer to finding solutions for the individual cases. The different stages of the portal will use electronic tools as well as classical learning and methods. It will work as a broker for high-quality contents and for study providers in the globe. Included will also be the evaluation of the learning process as well as deeper studies and development of new learning concepts. This also is a challenge: how to make the concept so attractive and still realistic that partners will commit themselves to it at an early stage of this project. 相似文献
7.
We apply the knowledge discovery process to the mapping of current topics in a particular field of science. We are interested in how articles form clusters and what are the contents of the found clusters. A framework involving web scraping, keyword extraction, dimensionality reduction and clustering using the diffusion map algorithm is presented. We use publicly available information about articles in high-impact journals. The method should be of use to practitioners or scientists who want to overview recent research in a field of science. As a case study, we map the topics in data mining literature in the year 2011. 相似文献
8.
In this article, we examine content supply as a public service strategy in Finland, one of the forerunner countries of digital terrestrial television in Europe. Regarding digitalization, European broadcasters face several options from full service to a specialized mission. The case at hand is the first full digital year of 2002 in Finland. The focus is on one of the traditional principles of public service broadcasting, the diversity of programming, as it is realized in the new, digital, multichannel environment. We examine content diversity by comparing channel profiles as well by analyzing indexes of the horizontal and vertical breadth and dissimilarity of programming. In a market of two public service and two commercial analogue generalist TV channels, the five new thematic digital channels have radically altered the amount of system-wide supply, but the diversity of programming has not suffered. This is due to the specializing strategy of the public service broadcaster. Its approach to focus on factual programming is clear in its digital output but can be detected in moderation also in its analogue supply. However, with the expected increase on commercial digital supply also in terrestrial networks, there is the possibility of the generalist public service broadcaster to turn into a fragmented one. 相似文献
9.
Eeva-Leena Kataja Linnea Karlsson Jukka M. Leppänen Juho Pelto Tuomo Häikiö Saara Nolvi Henri Pesonen Christine E. Parsons Jukka Hyönä Hasse Karlsson 《Child development》2020,91(2):e475-e480
We examined how infants’ attentional disengagement from happy, fearful, neutral, and phase-scrambled faces at 8 months, as assessed by eye tracking, is associated with trajectories of maternal depressive symptoms from early pregnancy to 6 months postpartum (decreasing n = 48, increasing n = 34, and consistently low symptom levels n = 280). The sample (mother–infant dyads belonging to a larger FinnBrain Birth Cohort Study) was collected between 5/2013–6/2016. The overall disengagement probability from faces to distractors was not related to maternal depressive symptoms, but fear bias was heightened in infants whose mothers reported decreasing or increasing depressive symptoms. Exacerbated attention to fearful faces in infants of mothers with depressive symptoms may be independent of the timing of the symptoms in the pre- and postnatal stages. 相似文献
10.
Eero A. Haapala Juuso Väistö Niina Lintu Tuomo Tompuri Soren Brage Kate Westgate 《Journal of sports sciences》2016,34(18):1699-1706
We investigated the associations of body fat percentage (BF%), objectively assessed moderate-to-vigorous physical activity (MVPA) and different types of physical activity assessed by a questionnaire with neuromuscular performance. The participants were 404 children aged 6–8 years. BF% was assessed using dual-energy x-ray absorptiometry and physical activity by combined heart rate and movement sensing and a questionnaire. The results of 50-m shuttle run, 15-m sprint run, hand grip strength, standing long jump, sit-up, modified flamingo balance, box-and-block and sit-and-reach tests were used as measures of neuromuscular performance. Children who had a combination of higher BF% and lower levels of physical activity had the poorest performance in 50-m shuttle run, 15-m sprint run and standing long jump tests. Higher BF% was associated with slower 50-m shuttle run and 15-m sprint times, shorter distance jumped in standing long jump test, fewer sit-ups, more errors in balance test and less cubes moved in box-and-block test. Higher levels of physical activity and particularly MVPA assessed objectively by combined accelerometer and heart rate monitor were related to shorter 50-m shuttle run and 15-m sprint times. In conclusion, higher BF% and lower levels of physical activity and particularly the combination of these two factors were associated with worse neuromuscular performance. 相似文献