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951.
Paul Bélanger 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1992,38(4):343-362
The aging of the population is accompanied by profound changes in life cycles, and it calls into question the models of institutional relationship between education, work and leisure time. After reviewing some concepts of aging, the author places the “training-work-retirement” triad in the context of the transformation of paid work and the new scenarios of ways in which people finally leave the labour market. Two questions are then asked: In what way may aging populations change the demand for adult continuing education? And, what is the significance of the present educational response to the problems posed by the aging of the population? 相似文献
952.
Authors Index
Authors index 相似文献953.
While a good deal of research has examined the uses of Twitter in journalism, comparably few research projects employ comparative research designs in order to provide new insights. The present study details Twitter use by public service broadcasters (PSBs) during recent national elections in Norway and Sweden. Utilizing quantitative analysis of social media content in tandem with qualitative interviews with key PSB journalists, the main results indicate that while the PSB organizations—the Norwegian NRK and the Swedish SVT—are both frequently contacted by “regular” citizens on Twitter, they seem to prefer to retweet and interact with journalists, politicians or other “elite” users. Compared with the interviews performed, the study uncovers an interesting tension as journalists often talk about the need to engage with “regular” users—a practice that is arguably in line with PSB regulations, but that is seldom adhered to in the contexts studied here. 相似文献
954.
Juan-Carlos Fernández-Molina Margarita Pérez-Pulido José-Luis Herrera-Morillas 《The Journal of Academic Librarianship》2017,43(3):184-192
Most information resources that make up university library collections are copyrighted works, which means that conflicts between such rights and the activities of libraries are common. The development of the digital setting has affected both sectors. On the one hand, it has led to changes in copyright legislation; on the other, it has affected the services provided by libraries, as they adapt to the new needs of users and to the characteristics of digital information. This paper aims to discover where the main points of collision between the two sides lie, and to what extent they are adequately resolved by the present legislation governing copyright. To this end we use a list of the main processes of academic libraries taken from quality manuals of a sample of Spanish university libraries. The results make manifest that the evolution of both sides is not yet balanced, and important maladjustments interfere with an adequate provision of services in academic libraries. Some are resolved through new legal proposals, but for many others there is no proper solution in sight. 相似文献
955.
News use and political discussion are often studied as important factors in understanding the effects of political efficacy on participation. However, measurements of external efficacy often blur distinctions between personal ability and government responsiveness. This study establishes a measure for perceptions of competence in the institutions of democratic government—government efficacy (GE). Drawing on panel survey data from the United States, confirmatory factor analysis introduces GE as a unique construct. Political efficacy dimensions are tested for their impact on news consumption, discussion, and political participation. Results add to the extant literature revolving the role of political efficacy on news use, discussion, and participation. 相似文献
956.
Marina Encheva Plamena Zlatkova Nilgün Özdamar Keskin İlker Vatansever 《International Information and Library Review》2017,49(2):145-161
Welcome to the Global Postcards column! We are so excited to bring you news and projects from around the world. In this column, our contributors from Bulgaria and Turkey bring us a comparative study of mobile and information literacy among students at two universities in those countries. In addition to presenting perceptions of students around these literacy concepts, their research project also highlights growing trends in the use of distance education and web-based study materials. Thanks to the contributors for this issue, and please keep the submissions coming!
If you would like to send a submission, please contact either of the column's co-editors: Jacqueline Solis, jsolis@email.unc.edu, and Robin Kear, rlk25@pitt.edu. 相似文献
957.
Ricardo?CamposEmail authorView authors OrcID profile Ga?l?Dias Alípio?Mário?Jorge Célia?Nunes 《Information Retrieval》2017,20(4):363-398
Despite a clear improvement of search and retrieval temporal applications, current search engines are still mostly unaware of the temporal dimension. Indeed, in most cases, systems are limited to offering the user the chance to restrict the search to a particular time period or to simply rely on an explicitly specified time span. If the user is not explicit in his/her search intents (e.g., “philip seymour hoffman”) search engines may likely fail to present an overall historic perspective of the topic. In most such cases, they are limited to retrieving the most recent results. One possible solution to this shortcoming is to understand the different time periods of the query. In this context, most state-of-the-art methodologies consider any occurrence of temporal expressions in web documents and other web data as equally relevant to an implicit time sensitive query. To approach this problem in a more adequate manner, we propose in this paper the detection of relevant temporal expressions to the query. Unlike previous metadata and query log-based approaches, we show how to achieve this goal based on information extracted from document content. However, instead of simply focusing on the detection of the most obvious date we are also interested in retrieving the set of dates that are relevant to the query. Towards this goal, we define a general similarity measure that makes use of co-occurrences of words and years based on corpus statistics and a classification methodology that is able to identify the set of top relevant dates for a given implicit time sensitive query, while filtering out the non-relevant ones. Through extensive experimental evaluation, we mean to demonstrate that our approach offers promising results in the field of temporal information retrieval (T-IR), as demonstrated by the experiments conducted over several baselines on web corpora collections. 相似文献
958.
Alejandro?BellogínEmail authorView authors OrcID profile Pablo?Castells Iván?Cantador 《Information Retrieval》2017,20(6):606-634
There is an increasing consensus in the Recommender Systems community that the dominant error-based evaluation metrics are insufficient, and mostly inadequate, to properly assess the practical effectiveness of recommendations. Seeking to evaluate recommendation rankings—which largely determine the effective accuracy in matching user needs—rather than predicted rating values, Information Retrieval metrics have started to be applied for the evaluation of recommender systems. In this paper we analyse the main issues and potential divergences in the application of Information Retrieval methodologies to recommender system evaluation, and provide a systematic characterisation of experimental design alternatives for this adaptation. We lay out an experimental configuration framework upon which we identify and analyse specific statistical biases arising in the adaptation of Information Retrieval metrics to recommendation tasks, namely sparsity and popularity biases. These biases considerably distort the empirical measurements, hindering the interpretation and comparison of results across experiments. We develop a formal characterisation and analysis of the biases upon which we analyse their causes and main factors, as well as their impact on evaluation metrics under different experimental configurations, illustrating the theoretical findings with empirical evidence. We propose two experimental design approaches that effectively neutralise such biases to a large extent. We report experiments validating our proposed experimental variants, and comparing them to alternative approaches and metrics that have been defined in the literature with similar or related purposes. 相似文献
959.
960.