My Recent Research PapersR. Aviv, Z. Erlich, G. Ravid, A. Geva, Network Analysis of Knowledge Construction in Asynchronous Learning Networks, Journal of Asynchronous Learning Networks 7 (3), 1-23, Sept 2003 The use of Asynchronous Learning Networks (ALN) makes the process of collaboration more transparent, as a transcript of conference messages can be used to assess both the collaborative process itself, and the role and contribution of the individual to the process. We consider three aspects of ALNs: the design; the quality of the resulting knowledge construction process; and the cohesion, role and power network structures. The design is evaluated according to the Social Interdependence Theory of Cooperative Learning. The quality of the knowledge construction process is evaluated through content analysis. The network structures are analyzed using Social Network Analysis of the response relations between participants during online discussions. In this research we analyze recorded data of two three-month-long ALNs of academic university courses: a formal, structured, closed forum and an informal, non-structured, open forum. We found that in the structured ALN, the knowledge construction process reached a very high level of critical thinking and developed a mesh of cohesive interconnected cliques. The students took on bridging and triggering roles, while the tutor had relatively little power. In the non-structured ALN, the knowledge construction process reached a low level of cognitive activity, few cliques were constructed, most of the students took on the passive role of teacher-followers, and the tutor was at the center of activity. These differences are statistically significant. We conclude that a well-designed ALN develops significant, distinct cohesion, role and power structures that lead the knowledge construction process to high levels of critical thinking. full paper in pdf R. Aviv, Z. Erlich, G. Ravid, Mechanisms and Architectures of Online Learning Networks, in Kinshuk,L.C., Sutinen, E., Sampson, D., Aedo, I., Uden, L., & Kahekonen E. (Eds.), The 4th IEEE International Conference on Advanced Learning Technologies (ICALT), pp. 400-404, Joensuu, Finland (2004). Abstract Online communities are described in terms of collections of virtual neighborhoods, each of which is a sub-set of interdependent members. The significant virtual neighborhoods are revealed by fitting parametric Markov Field models (p*) to the response relations of the communities. The underlying theoretical mechanisms are then deduced by matching the revealed virtual neighborhoods with the predictions of network emergence theories. We demonstrate that the underlying mechanisms are related to specific design features of the communities. This method can be extended to other relations in online communities and to longitudinal analysis, and applied to real-time monitoring of online communications. full paper in pdf R. Aviv, Z. Erlich, G. Ravid, Reciprocity Analysis of Online Learning Networks, Journal of Asynchronous Learning Networks, 9 (4), 1-13, 2005 Abstract This paper examines the question of the existence of reciprocity in online learning networks. We analyzed the response relations between participants of 75 online learning networks at the Open University of Israel. Specifically, we ask whether the observed reciprocity of responses can be explained by random selection of partners to respond to, or whether a reciprocal selection process of partners is at work. The possible selection process is modeled as constraints on the random response process. The observed reciprocities were compared with three base line network models. Model 1 allowed actors to select partners to respond to at random, with no constraints. Model 2 restricted randomness by a holding the global response capacity of all actors fixed at the observed value. Model 3 restricted randomness by fixing the response capacities of actors to their observed values. The expected values of reciprocities for each of the models were computed analytically (models 1 and 2) and by simulation (model 3). In all 75 online learning networks, the observed reciprocities significantly deviate from the expected values. The implications are: (i) reciprocal selection processes are at work in online learning networks; (ii) the selection processes can be partially described in terms of the response capacities of actors; and (iii) other factors are required to fully capture the nature of this process. We discuss a possible theoretical explanation for reciprocity in online networks, based on its broadcast nature, and the practical implications for online collaborative learning. Full paper in pdf R. Aviv, Z. Erlich, G. Ravid, Response Neighborhoods in Online Learning Networks, Educational Technology & Society, 8(4), Oct. 2005 Abstract Response mechanisms and neighborhoods in networks of online learners are revealed by Statistical Analysis of p* Markov Models for the Networks. Our analysis shows that the minimal-effort techniques presented in hunt-for-social-capital mechanism controls a major behavior of the networks: negative tendency to respond. Differences in the goals, interdependence and pre-assigned roles features of the designs lead to the development of different mechanisms: cognition balance and peer pressure in a team like network, exchange mechanism in a Q&A type forum. These differences lead to the formation of transitive and star-like response triads in the team network and mutual dyads in the Q&A forum. These micro structures lead to differences in the macro-structures of the networks and the buildup of collaborative knowledge. This work can be extended to other types of mechanisms and networks. full paper in pdf Haythornthwaite, C. Aviv, R., Collaboration Issues in Small, Distributed Groups, Position Paper Prepared For Sloan-C, Victoria BC, July 2005 Abstract This paper addresses collaboration attributes in small, distributed groups. The emphasis is on the purposes and enactment of collaboration in online learning settings. Like Garrison (2005), the assumption is that “the goal of the collaboration is to create a community of inquiry where students are fully engaged in collaboratively constructing meaningful and worthwhile knowledge.” However, within that range, we highlight here that there are attributes of collaboration that can affect the expression of the engagement in knowledge creation, and thus the eventual achievement of a community of inquiry. In identifying these attributes, we draw on research and theory about collaborative learning, computer-supported collaborative learning (CSCL), knowledge construction, group learning, scientific and interdisciplinary collaboration, and computer-mediated communication. full paper in pdf Swan, K., Schenker, J. Lin, Y. M., Shea, P. & Aviv, R. Student Satisfaction with Online Leraning: A Concept Analysis, Proc. Annual Meeting of the American, Educational Research Association, San Francisco, April 2006. Abstract This study is premised on the notion that the quality of a learning experience derives from a process of co-production between the learner and the learning-environment, and that therefore the quality of online learning must be understood from the learner’s perspective. It explores what students value in online learning by identifying emergent themes in 1598 student responses to a request for “Additional Comments” in end-of-term evaluations. Quantitative content analyses are used to calculate frequencies of reference to the identified constructs as well as correlations among them. Results indicate the importance of instructors and instructor feedback to student satisfaction with online learning. full paper in pdf Yoav Yair, Reuven Aviv, Gilad Ravid, Roy Yaniv, Baruch Ziv, Colin Price,Evidence for synchronicity of lightning activity in networks of spatially remote thunderstorms, Journal of Atmospheric and Solar-Terrestrial Physics 68 (2006) 1401–1415 Abstract Visual observations by space shuttle astronauts have described a phenomenon in which spatially distant thunderstorm cells seem to reciprocally "ignite" lightning flashes in a semi-cyclic sequence. Lightning occurring in one cell is immediately followed by lightning in other cells, separated by tens or hundreds of kilometers. We present quantitative analysis of lightning observations conducted within the framework of the MEIDEX-sprite campaign on board the space shuttle Columbia in January 2003 (Yair et al., 2003). Video footage of 6 storm systems with varying flash rates, which occurred over Africa, South America, Australia and the Pacific Ocean were analyzed. It is found that when the storm flash rate was high, lightning activity in horizontally remote electrically active cells became clustered, with bursts of nearly simultaneous activity separated by quiet periods. The recurrence time was ~2.5 seconds, close to the previously reported time delay between consecutive ELF transient signals in the Schumann resonance range (Füllekrug, 1995). We propose that this behavior is similar to the collective dynamics of a network of weakly coupled limit-cycle oscillators (Strogatz, 2000). Thunderstorm cells embedded within a mesoscale convective system (MCS) constitute such a network, and their lightning frequency is best described in terms of phase-locking of a globally coupled array (Kourtchatov et al., 1995). Comparison of basic parameters of the lightning networks with predictions of random-graph models reveals that the networks cannot be described by the classical random-graph model (Erdos and Renyi, 1960), but are more compatible with generalized random-graphs with a prescribed degree distribution (Newman et al., 2001) that exhibit a high clustering coefficient and small average path lengths. Such networks are capable of supporting fast response, synchronization and coherent oscillations (Lago-Fernandez et al., 2000). Several physical mechanisms are suggested to explain the observed phenomenon. full paper in pdf Yair, Y., Aviv, R., Price, C., Asfur, M. and Ravid, G, Can spontaneous synchronization of lightning flashes occur in a network of distant thunderstorms? Geophys. Res. Abs., vol 9, 03235, EGU General Assembly, Vienna, 15-20 April, (2007), SRef-ID: 1607-7962/gra/EGU2007-A-03235 Abstract There is now a considerable body of theoretical and experimental research that relates the properties of complex dynamical phenomena in nature to those described by network theory [Strogatz, Nature, 2001]. In this context, a network is a system composed of several separate interacting entities, relating to each other in different modes with varying levels of complexity. We propose that thunderstorm cells embedded within mesoscale convective system (MCS) constitute a network, and their lightning frequency is closely connected. Analysis of space-shuttle video footage of 6 storm systems with varying flash rates showed that when the storm flash rate was high, lightning activity in horizontally remote electrically active cells became clustered, with bursts of nearly simultaneous activity separated by quiet periods [Yair et al., JASTP, 2006]. This behavior is similar to the collective dynamics of a network of weakly coupled limit-cycle oscillators, best described in terms of phase-locking of a globally coupled array. We expand our analysis to other data-sets of thunderstorm activity, derived from ground-based lightning location systems, and compare the basic parameters of the observed lightning rate with predictions of random-graph network models. Initial results suggest that network theory parameters of lightning activity in distant cells exhibits a high clustering coefficient and small average path lengths. This type of networks is capable of supporting fast response, synchronization and coherent oscillations. Several physical mechanisms are suggested to explain the observed phenomenon. R. Aviv, G. Ravid, Z. Erlich, Randomness and Clustering of Responses in Online Learning Networks, Proceedings of the Communication, Internet, and Information Tecnology 2007, Banff, July 2-4, 2007) Abstract The goal of this research is to explore the nature of the response relation in online learning networks. We ask whether actors choose their response partners at random or whether certain special mechanisms are at work. We compare the observed values of clustering of responses in 95 online learning networks with the predictions of two suitable Random Graph models. All the online distance learning networks exhibit clustering that is incompatible with the random choices of response partners, with no constraints on the response capacities of actors. But the observed clustering in all networks is compatible with the random choices of response partners subject to constraints on their total response capacities. We provide a possible explanation for this behavior, based on the nature and goal of the online learning networks, and discuss the practical implications for online distance education. full paper in pdf Zippy Erlich, Reuven Aviv, Open Source Software: Strengths and Weaknesses, in Handbook on Research on Open Source Software: Technological, Economic and Social perspectives, pp 184-196, Information Science Reference, Hershey, New York, 2007 Abstract The philosophy underlying open source software (OSS) is enabling programmers to freely access the software source by distributing the software source code, thus allowing them to use the software for any purpose, to adapt and modify it, and redistribute the original or the modified source for further use, modification, and redistribution. The modifications, which include fixing bugs and improving the source, evolve the software. This evolutionary process can produce better software than the traditional proprietary software, in which the source is open only to a very few programmers and is closed to everybody else who blindly use it but cannot change or modify it. The idea of open source software arose about 20 years ago and in recent years is breaking out into the educational, commercial, and governmental world. It offers many opportunities when implemented appropriately. The chapter will present a detailed definition of open source software, its philosophy, its operating principles and rules, and its strengths and weaknesses in comparison to proprietary software. A better understanding of the philosophy underlying open source software will motivate programmers to utilize the opportunities it offers and implement it appropriately. full paper in pdf R. Aviv, G. Ravid, Y. Yair,Transient Synchronicity and Coupling of Lightning Flashes. Proc. AGU Fall Meeting, 10-14 December, 2007, 2007, San Francisco, California Abstract We analyzed sequences of lightning flashes in Mediterranean winter thunderstorm, based on data obtained during the 2004/5 and 2005/6 seasons from ground-based lightning location systems. Patterns of clustering and synchronicity of flashes in individual thunderstorm cells, separated by tens to hundreds of kilometers, was identified. This is similar to early results based on space shuttle lightning images [Yair et al., 2006], hinting at a possible mutual electromagnetic coupling of remote thunderstorms. We developed a theoretical model that is based on the "leaky fire and integrate" approach, commonly used in models of neural activity, in order to simulate the flashing behavior of a coupled network of thunderstorm cells. In this type of network, the intensity of the electric field Ei within thunderstorm (i) grows with time until it reaches the critical breakdown value, generates a lightning flash while its electric field drops to zero, simultaneously adding a delta-E to the intensity of the internal electric field in all thunderclouds (Ej,k,l…) that are linked to it. The value of delta-E is inversely proportional to the distance between the "firing" cloud i and its neighbors j,k,l... We assumed that all thunderstorms are identical and occupy a grid with random spacing and organization. Several topologies of the thunderstorm network were tested with varying degrees of coupling, assuming a fixed probability of links between active cells. The results suggest that when the coupling in the network is higher than a certain critical value, all thunderstorm cells will eventually flash in a synchronized manner. The physical mechanisms that are possibly interacting in such a network of coupled thunderclouds will be discussed. R. Aviv, Z. Erlich, G. Ravid , Analysis of Transitivity and Reciprocity in Online Collaboration Networks, CONNECTIONS, June 2008 Abstract The goal of this research is to clarify whether network emergence mechanisms common in social networks are also involved in structuring online collaboration networks. We compare the observed values of reciprocity and transitivity in 95 online collaboration networks and 40 social networks with predictions of Random Graph models. All the tested networks exhibit reciprocities that significantly deviate from the predictions of the random graph models. All the online collaboration networks and some of the social networks – not all - exhibit transitivity compatible with generalized random graph models. We conclude that exchange mechanisms, responsible for reciprocity, are at work in all networks, but there is no evidence for cognition balance mechanisms in any of the tested online collaboration networks. We provide possible explanations for these behaviors, based on the broadcast nature of the online collaboration networks, and the practical implications for online collaborative learning. full paper in pdf R. Aviv, Learning by Community of Inquiry: A Hypothetical, Implementable Scenario, (Work in Progress December 2008) Abstract This paper describe a theory based design of collaborative learning scenario, implementing the Community of Inquiry Model (COI). Specifically, the three important elements of the COI model are emphasized: Cognitive Presence constructs – triggering events, exploration, integration and resolution – are built into the design; Social Presence constructs – open communication and group cohesion – are emphasized. The overall control is provided by strong Teaching Presence constructs - instructional management and some direct instruction. Incorporating these constructs into the scenario is guided by the set of principles specified by Garrison. draft in pdf |