16127213
Supporting interactive collaboration on the Web with CORK
Abstract The World Wide Web has served as a medium for collaboration since its inception. Web-based collaboration has, however, been dominated by systems supporting asynchronous activities such as sharing documents and participating in discussion forums. Supporting interactive, synchronous collaboration on the Web has proven much more challenging. In this paper we describe three of the challenges encountered in the context of supporting network-based collaboration among middle and high school science students: integrating synchronous and asynchronous modes of interaction, minimizing consumption of bandwidth, and adapting non-collaborative software components for collaborative use. We then present the Content Object Replication Kit, a toolkit for building interactive Java-based collaborative systems for use on the Web.
15595014
Notification and awareness: synchronizing task-oriented collaborative activity
People working collaboratively must establish and maintain awareness of one another's intentions, actions and results. Notification systems typically support awareness of the presence, tasks and actions of collaborators, but they do not adequately support awareness of persistent and complex activities. We analysed awareness breakdowns in use of our Virtual School system--stemming from problems related to the collaborative situation, group, task and tool support--to motivate the concept of activity awareness. Activity awareness builds on prior conceptions of social and action awareness, but emphasizes the importance of activity context factors like planning and coordination. This work suggests design strategies for notification systems to better support collaborative activity.
2269827
Training wheels in a user interface
New users of high-function application systems can become frustrated and confused by the errors they make in the early stages of learning. A training interface for a commercial word processor was designed to make typical and troublesome error states “unreachable,” thus eliminating the sources of some new-user learning problems. Creating a training environment from the basic function of the system itself afforded substantially faster learning coupled with better learning achievement and better performance on a comprehension post-test. A control group spent almost a quarter of their time recovering from the error states that the training interface blocked off. We speculate on how this training strategy might be refined, and more generally, on how function should be organized in a user interface.
9978523
Community collective efficacy: structure and consequences of perceived capacities in the Blacksburg Electronic Village
Bandura's social cognitive construct "perceived self-efficacy" has been used widely to understand individual behavior as a function of domain-specific beliefs about personal capacities. Collective efficacy is the extension of the self-efficacy construct to organizations and groups; it refers to beliefs about collective capacities in specific domains. Our research is investigating the use of collective efficacy in understanding attitudes and behaviors of members of proximal residential communities with respect to issues like attachment, engagement, and sociality, specifically as modulated by use of the Internet and community networks. This paper describes our analysis of the structure and external validity of the collective efficacy construct.
148806746
Human-computer interaction: psychology as a science of design.
7723669
Better home shopping or new democracy?: evaluating community network outcomes
This is a perspective paper on community networks - socio-technical infrastructures supporting villages, towns, and neighborhoods. Community networking is well-established, world wide, and addresses critical societal issues, such as the “crisis of community” and the sociality of the Internet. However, community network projects have not emphasized evaluation. Relatively little is known about the economic, social, and psychological consequences of community networks for the individuals, groups, and communities served. Evaluating community networks is a momentous mutual opportunity for the development of CHI evaluation methodologies and for bringing technical CHI expertise to bear on societal issues.
11544923
Unparsing RDF/XML
It is difficult to serialize an RDF graph as a humanly readable RDF/XML document. This paper describes the approach taken in Jena 1.2, in which a design pattern of guarded procedures invoked using top down recursive descent is used. Each procedure corresponds to a grammar rule; the guard makes the choice about the applicability of the production. This approach is seen to correspond closely to the design of an LL(k) parser, and a theoretical justification of this correspondence is found in universal algebra.
39105600
Estimating the Reliability of Regeneration-Based Replica Control Protocols
The accessibility of vital information can be enhanced by replicating the data on several sites and employing a consistency control protocol to manage the replicas. The reliability of a replicated data object depends on maintaining a viable set of current replicas. When storage is limited, it may not be feasible to simply replicate a data object at enough sites to achieve the desired level of reliability. Regeneration approximates the reliability provided by additional replicas for a modest increase in storage costs, and is applicable whenever a new replica of a data object can be created faster than a system failure can be repaired. Regeneration enhances reliability by creating new replicas on other sites in response to site failures. Several strategies for replica maintenance are considered, and the benefits of each are analyzed using simulation and both algebraic and numeric solutions to systems of differential equations. >
14571844
The process of ISD methodology selection and use: a case study
This paper provides empirically-based explanations for the observed low, and partial, use of information systems development (ISD) methodologies. The research reported in this paper examines the process of methodology selection and use in an intensive field study of the early stages of systems development and notes ongoing adaptation of methodologies in response to changing contingencies. The paper concludes that, in many circumstances, methodology adaptation is a necessary part of successful systems development. It also suggests that deeper understanding of the attitudes of different stakeholders to selecting and using ISD methodologies may help to explain this adaptation.
5584278
Reinforcement Learning Task Clustering
14983459
Fixed vs. Dynamic Sub-Transfer in Reinforcement Learning
We survey various task transfer methods in Qlearning and present a variation on fixed sub-transfer which we call dynamic sub-transfer. We discuss the benefits and drawbacks of dynamic sub-transfer as compared with the other transfer methods, and we describe qualitatively the situations where this method would be preferred over the fixed version of sub-transfer. We test this method against several other transfer methods in a simple three room grid world where portions of the source’s policy are relevant to the target task and other portions are not. In this situation we found that dynamic sub-transfer converged to the optimal solution, avoiding the suboptimality inherent in fixed sub-transfer, while also avoiding some of the convergence problems often experienced by fixed sub-transfer.