Preference-inconsistent recommendations: An effective approach for reducing confirmation bias and stimulating divergent thinking?

The Web is a perfect backdrop for opinion formation as a multitude of different opinions is publicly available. However, the different opinions often remain unexploited: Learners prefer preference-consistent over preference-inconsistent information, a phenomenon called confirmation bias. Two experiments were designed to test whether technologies such as recommender systems can be used to overcome this bias. The role of preference-inconsistent recommendations was explored by comparing their influence to a condition with preference-consistent recommendations and to a control condition without recommendations. In Study 1, preference-inconsistent recommendations led to a reduction of confirmation bias and to a more moderate view of the controversial topic of neuro-enhancement. In Study 2, we found that preference-inconsistent recommendations stimulated balanced recall and divergent thinking. Together these studies showed that preference-inconsistent recommendations are an effective approach for reducing confirmation bias and stimulating divergent thinking. In conclusion, future research and practical implications are discussed.     

Improving quality and quantity of contributions: Two models for promoting knowledge exchange with shared databases

Shared databases are used for knowledge exchange in groups. Whether a person is willing to contribute knowledge to a shared database presents a social dilemma: Each group member saves time and energy by not contributing any information to the database and by using the database only to retrieve information which was contributed by others. But if all people use this strategy, then the database will be empty and, hence, useless for every group member. Based on theoretical approaches, two models for fostering the information-sharing behavior of database users are presented. One for enhancing the quality of database contents, and one for enhancing the quantity of those contents. The models take into account the following factors: the kinds of rewards the participants obtain for contributing information, the individual costs associated with this contribution, the prospective metaknowledge about the importance of one’s own information to the others, and the retrospective metaknowledge about how much others contributed to and retrieved from the database. These factors enhance the quantity of database contents as well as their quality.     

Group awareness and self-presentation in computer-supported information exchange

A common challenge in many situations of computer-supported collaborative learning is increasing the willingness of those involved to share their knowledge with other group members. As a prototypical situation of computer-supported information exchange, a shared-database setting was chosen for the current study. This information-exchange situation represented a social dilemma: while the contribution of information to a shared database induced costs and provided no benefit for the individual, the entire group suffered when all members decided to withhold information. In order to alleviate the information-exchange dilemma, a group-awareness tool was employed. It was hypothesized that participants would use group awareness for self-presentational purposes. For the examination of this assumption, the personality variable ‘protective self-presentation’ (PSP) was measured. An interaction effect of group awareness and PSP was found: when an awareness tool provided information concerning the contribution behavior of each individual, this tool was used as a self-presentation opportunity. In order to understand this effect in more detail, single items of the PSP-scale were analyzed.     

An approach to power transformer asset management using health index - [feature article]

The Health Index represents a practical tool that combines the results of operating observations, field inspections, and site and laboratory testing to manage the asset and prioritize investments in capital and maintenance plans.     

CSCL for intellectually disabled pupils: Stimulating interaction by using a floor control mechanism

Computer-supported collaborative learning has an unexploited potential of becoming an effective learning method for pupils with intellectual disabilities. This paper aims at showing how some specific requirements of this target group may be met by structuring a learning situation with the help of floor control, which restricts the opportunities of a learning dyad to act simultaneously within the learning environment. It was expected that floor control could improve communication between pupils with intellectual disabilities by explicitly structuring and restricting activities in the learning environment and making it necessary for the pupils to communicate. To examine if floor control really supports the collaboration process in the hypothesized way, two different versions of a CSCL environment were implemented and compared. The results revealed improved task-related communication and a higher quality of interaction outcomes.     

The need for considering multilevel analysis in CSCL research—An appeal for the use of more advanced statistical methods

Per definition, CSCL research deals with the data of individuals nested in groups, and the influence of a specific learning setting on the collaborative process of learning. Most well-established statistical methods are not able to analyze such nested data adequately. This article describes the problems which arise when standard methods are applied and introduces multilevel modelling (MLM) as an alternative and adequate statistical approach in CSCL research. MLM enables testing interactional effects of predictor variables varying within groups (for example, the activity of group members in a chat) and predictors varying between groups (for example, the group homogeneity created by group members’ prior knowledge). So it allows taking into account that an instruction, tool or learning environment has different but systematic effects on the members within the groups on the one hand and on the groups on the other hand. The underlying statistical model of MLM is described using an example from CSCL. Attention is drawn to the fact that MLM requires large sample sizes which are not provided in most CSCL research. A proposal is made for the use of some analyses which are useful.     

The effect of strength and endurance training on gait, balance, fall risk, and health services use in community-living older adults

BACKGROUND: The study tested the effect of strength and endurance training on gait, balance, physical health status, fall risk, and health services use in older adults. METHODS: The study was a single-blinded, randomized controlled trial with intention-to-treat analysis. Adults (n = 105) age 68-85 with at least mild deficits in strength and balance were selected from a random sample of enrollees in a health maintenance organization. The intervention was supervised exercise (1-h sessions, three per week, for 24-26 weeks), followed by self-supervised exercise. Exercise groups included strength training using weight machines (n = 25), endurance training using bicycles (n = 25), and strength and endurance training (n = 25). Study outcomes included gait tests, balance tests, physical health status measures, self-reported falls (up to 25 months of follow-up), and inpatient and outpatient use and costs. RESULTS: There were no effects of exercise on gait, balance, or physical health status. Exercise had a protective effect on risk of falling (relative hazard = .53, 95% CI = .30-.91). Between 7 and 18 months after randomization, control subjects had more outpatient clinic visits (p < .06) and were more likely to sustain hospital costs over $5000 (p < .05). CONCLUSIONS: Exercise may have beneficial effects on fall rates and health care use in some subgroups of older adults. In community-living adults with mainly mild impairments in gait, balance, and physical health status, short-term exercise may not have a restorative effect on these impairments.     

Integrating vestibular displays for VE and airborne applications

Designing effective human machine interfaces is one of the more challenging and exciting issues facing engineers today. Many virtual environment (VE) designers approach this problem by examining the way humans interact with their natural environment. In essence, they have attempted to mimic the various ways humans use their senses to gather information. This approach seeks to present task relevant information in a form that is familiar, compellingly realistic, and intuitive. We have taken this design approach for the development of a direct vestibular display. We intend to provide self motion information to the vestibular system in a static virtual environment-that is, to simulate not only the look but also the feel of such sensations as turning and swaying. The article explains our rationale and method for doing so and reports results from our experiments using a visual vestibular interface