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

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

The arrival of the frequent: how bias in genotype-phenotype maps can steer populations to local optima

Genotype-phenotype (GP) maps specify how the random mutations that change genotypes generate variation by altering phenotypes, which, in turn, can trigger selection. Many GP maps share the following general properties: 1) The number of genotypes $N_G$ is much larger than the number of selectable phenotypes; 2) Neutral exploration changes the variation that is accessible to the population; 3) The distribution of phenotype frequencies $F_p=N_p/N_G$, with $N_p$ the number of genotypes mapping onto phenotype $p$, is highly biased: the majority of genotypes map to only a small minority of the phenotypes. Here we explore how these properties affect the evolutionary dynamics of haploid Wright-Fisher models that are coupled to a simplified and general random GP map or to a more complex RNA sequence to secondary structure map. For both maps the probability of a mutation leading to a phenotype $p$ scales to first order as $F_p$, although for the RNA map there are further correlations as well. By using mean-field theory, supported by computer simulations, we show that the discovery time $T_p$ of a phenotype $p$ similarly scales to first order as $1/F_p$ for a wide range of population sizes and mutation rates in both the monomorphic and polymorphic regimes. These differences in the rate at which variation arises can vary over many orders of magnitude. Phenotypic variation with a larger $F_p$ is therefore be much more likely to arise than variation with a small $F_p$. We show, using the RNA model, that frequent phenotypes (with larger $F_p$) can fix in a population even when alternative, but less frequent, phenotypes with much higher fitness are potentially accessible. In other words, if the fittest never `arrive' on the timescales of evolutionary change, then they can't fix. We call this highly non-ergodic effect the `arrival of the frequent'.Comment: full paper plus supplementary material

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

Population characteristics and habitat suitability of Asian elephants (Elephas maximus Linnaeus, 1758) in the Khao Yai National Park, Thailand

The aim of this study was to investigate the population and habitat of wild elephants in the Khao Yai National Park, to provide elephant population densities using the line transect method. Habitat suitability was also assessed based on the data obtained from the location of the species during monthly ranger patrol across the park area, with the rate of dung decay used for population calculation. The population structure and age class were studied by direct observation to estimate the population trend. On the basis of 116 systematic transect lines that were 2 km in length and separated by 500-m intervals, a total of 1,209 elephant dung piles were found in more than 213.20 km. The analysis of the combined data showed that the dung density was 531.49 dung piles/km 2, with a decay rate of 0.0039 dung piles/day based on 56 dung piles checked every 7 days. The annual data showed that the population density was 0.15 individuals/km 2. The population structure comprising  calf:juvenile:subadult:adult was 1: 1.09:1.14:2.10; the sex ratio of adult male to adult female elephants was 1:1.10; and the ratio of reproductive ability among adult females, juveniles, and calves was 1.00:0.99:0.90. The combined data also showed that the main environmental factor affecting the presence of the animals was salt lick sites. The pooled data analysis found that the habitat most suitable for the elephants covered an area of 220.59 km 2. The habitat suitability, based on the dry season appearance data, covered an area of 258.64 km 2, whereas during the wet season, it covered an area of 517.45 km 2. As the most suitable habitat for elephants appears around the park boundary, habitat improvements for wild elephants should address the central areas of the national park. A greater emphasis should be placed on creating salt licks, being far from human activity sites

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

Assessment of the minimalist approach to computer user documentation

The minimalist approach (Carroll, 1990a) advocates the development of a radically different type of manual when compared to a conventional one. For example, the manual should proceed almost directly to procedural skills development rather than building a conceptual model first. It ought to focus on authentic tasks practised in context, as opposed to mock exercises and isolated practice. In addition, it should stimulate users to exploit their knowledge and thinking, as opposed to imposing the writer's view and discussing everything that users should see or know.\ud \ud In the first part of the paper the construction of a tutorial based on the minimalist principles is described. A parallel is drawn with constructivism with which minimalism shares important notions of instruction. In the second part, an experiment is described in which the minimal manual was tested against a conventional one. The outcome favoured the new manual. For example, minimal manual users completed about 50% more tasks successfully on a performance test and displayed significantly more self-reliance (e.g. more self-initiated error-recoveries, and fewer manual consultations)