Supporting peer interaction in online learning environments

This paper reports two studies into the efficacy of sentence openers to foster online peer-to-peer interaction. Sentence openers are pre-defined ways to start an utterance that are implemented in communication facilities as menu’s or buttons. In the first study, typical opening phrases were derived from naturally occurring online dialogues. The resulting set of sentence openers was implemented in a semi-structured chat tool that allowed students to compose messages in a freetext area or via sentence openers. In the second study, this tool was used to explore the students’ appreciation and unprompted use of sentence openers. Results indicate that students hardly used sentence openers and were skeptical of their usefulness. Because both measures were negatively correlated with students’ prior chat experience, optional use of sentence openers may not be the best way to support students’ online interaction. Based on these findings, alternative ways of using sentence openers are discussed and topics for further research are advanced

Interactive television or enhanced televisiion? : the Dutch users interest in applications of ITV via set-top boxes

This paper is both an analysis of the phenomenon of interactive television with background concepts of interactivity and television and a report of an empirical investigation among Dutch users of set-top-box ITV. In the analytic part a distinction is made between levels of interactivity in the applications of ITV. Activities labelled as selection, customisation, transaction and reaction reveal low levels of interactivity. They may be called ‘enhanced television’. They are extensions of existing television programmes that keep their linear character. Activities called production and conversation have the potential of higher interactivity. They may lead to ‘real’ interactive television as the user input makes a difference to programmes. It is suggested that so-called hybrid ITV– TV combined with telephone and email reply channels- and (broadband) Internet ITV offer better opportunities for high interactivity than set-top-box ITV. \ud The empirical investigation shows that the demand of subscribers to set-top-box ITV in the Netherlands matches supply. They favour the less interactive applications of selection and reaction. Other striking results are that young subscribers appreciate interactive applications more than the older ones and that those with a low level of education prefer these applications more than high educated subscribers. No significant gender differences were found

Effects Of Low Metal Levels On A Clonal Hydroid

We frequently require sensitive bioassay techniques with which to study the effects of marine contaminants at environmentally realistic concentrations. Unfortunately, it is difficult to achieve sensitivity and precision in an organism amenable to indefinite periods of laboratory culture. Results from different laboratories are often extremely variable: LC50 values for the same substance, using the same organism, may differ by two or even three orders of magnitude (Wilson, Cowell & Beynon, 1975). Moreover, some of the most sensitive bioassay organisms require nutrient media, which may alter the availability and toxicity of metals by complexing them (Jones, 1964; Kamp-Nielsen, 1971; Hannan & Patouillet, 1972) and often contain metal impurities at significant levels (Albert, 1968; Steeman Nielsen & Wium Anderson, 1970). The object of the work reported here has been to develop a technique by which these problems might be minimized or avoided. Hydroids were chosen as bioassay organisms for a variety of reasons. They are tolerant but sensitive to small variations in their chemical environment. Techniques for growing hydroids are simple and they can be cultured under conditions of near optimal temperature, salinity and food supply, thus minimizing the errors frequent in bioassay work arising from variations in the history of the test organisms, their size, sex or physiological state. An important source of variability in all work with organisms is that inherent in the genetic material, but with hydroids this can be avoided by the use of a single clone

Towards systematic understanding of institutional interests in current agenda items at the world radiocommunication conference

The World Radiocommunication Conference (WRC) serves as a forum to negotiate, review, and revise the Radio Regulations (RR), an international treaty and one of the most difficult regulations for radiocommunication services. RR is complex since it includes intergovernmental issues in relation to regulation covering technical, legal and societal aspects. A large number of parties are interested and involved in revising RR and creating supranational instruments for optimal management of the spectrum. As a consequence, it can be difficult for one involved stakeholder to see its own position and other relevant issues directly influencing them in relation to the whole work of WRC and its subprocesses. A systematic analysis of the main decision-making process would contribute to better understanding of the role of WRC and positions of the involved parties. The aim of the paper is to contribute to better understanding of the role of the WRC with a focus on the current agenda items. Agenda items are specified issues from RR that need to be handled at an actual conference. The point of departure is using the institutional analysis and development (IAD) framework [see Ostrom (2011)] to gain a suitable institutional overview of the main decision-making process and its sub-processes. The IAD framework has the capacity to explain jointly produced outcomes, such as negotiating an international treaty depending on multiple inputs and different priority levels. Also, it can be used to enhance the understanding of WRC matters in order to improve the decision-making process by focusing on the main interactions and involved parties in relation to the possible outcomes of the WRC. The paper is based on data obtained from historical documents, content analysis, literature review, observations, and interviews. The results of this paper illustrate the benefits of the IAD framework in the context of the WRC, especially for the process of agenda setting and study cycles. The practical implications are important for policy makers, for example, since it highlights critical actors, events, and interactions aligned with the main activities of WRC. A stakeholder will better understand its own position and its possibility for control, both in relation to the overall process and the sub-processes important for agenda items in which it has an interest. It will gain understanding not only of the overall role of WRC, but also of its own possibilities to intervene during the process of revision of RR so that it could protect its interests - e.g., with more proper contribution in the suitable forums with the expected outcome. --Radio Regulations (RR),institutional analysis and development (IAD) framework,World Radiocommunication Conference (WRC),WRC agenda items,decision situation

Forecasting inflation: An art as well as a science!

In this study we build two forecasting models to predict inflation for the Netherlands and for the euro area. Inflation is the yearly change of the Harmonised Index of Consumer Prices (HICP). The models provide point forecasts and prediction intervals for both the components of the HICP and the aggregated HICP-index itself. Both models are small-scale linear time series models allowing for long run equilibrium relationships between HICP components and other variables, notably the hourly wage rate and the import or producer prices. The model for the Netherlands is used to generate the Dutch inflation projections over a horizon of 11-15 months ahead for the eurosystem’s Narrow Inflation Projection Exercise (NIPE). The recursive forecast errors for several forecast horizons are evaluated for all models, and are found to outperform a naive forecast and optimal AR models. Moreover, the same result holds for the Dutch NIPE projections, which have been provided quarterly since 1999. The direct and aggregation methods to predict total HICP inflation perform about equally goodmodel selection, time series models, aggregation

Status of demersal fishery resources in the Gulf of Thailand

Data from trawl surveys (1961 - 95) and annual production statistics (1971 - 95) were used to examine the status of demersal fishery resources in the Gulf of Thailand. Analyses were focused on biomass trends, population parameters and exploitation rates of dominant species, and assessment of excess capacity from fishing effort and yield estimates. The results indicate by 1995, the trawlable biomass in the Gulf had declined to only about 8.2% of the biomass level in 1961. The substantial decline is true for major components (demersal fish and trash fish) and species groups (Nemipterus spp., Priacanthus spp., Saurida spp. and squids) comprising trawlable biomass. Estimates of exploitation rate (E) for 23 species indicate that most (particularly demersals) are over-fished. By 1995, 21 of the species had E values of 0.79 and higher. Analyses of standardized fishing effort and yield using the Fox model indicate that the 1995 fishing effort was about twice the level needed to harvest the maximum sustainable yield. Overall, the results illustrate that the resources are severely over-exploited. The excess demersal fishing effort is estimated to be about 50% of the number of registered boats in 1995.Fishery resources, Demersal fisherie, Fishery surveys, Biomass, Population density, Shrimp fisheries, Catch/effort, ISEW, Thailand Gulf,