social network analysis of 45000 schools: a case study about technology enhanced learning in europe
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Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-1
CUELC
Ruth Breuer, Ralf Klamma, Yiwei Cao, Riina VuorikariEC-TEL 2009, Nice, France, October 1, 2009
Social Network Analysis of 45000 (50000+) Schools:
A Case Study of Technology Enhanced Learning in Europe
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-2
CUELC
Social Network Analysis Contributions to EC-TEL so far
2006 - Klamma, Spaniol, Cao, Jarke: Pattern-Based Cross Media Social Network Analysis for Technology Enhanced Learning in Europe– Media Bases as research tools for TEL– SNA as research methodology for TEL
2007 – Programme Chair 2008 - Petrushyna, Klamma: No Guru, No Method, No Teacher: Self-
Oberservation and Self-Modelling of E-Learning Communities– In-depth Analysis of a Media Base for TEL– Combination of SNA and content-based measures
2009 - Breuer, Klamma, Cao, Vuorikari: Social Network Analysis of 45000 Schools: A Case Study of TEL in Europe– eTwinning database of European cooperation between schools– SNA as a tool for teachers– Visualization and Usability
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-3
CUELC
Agenda
Social Network Analysis – Tools for teachers? eTwinng Scenario and teacher-oriented SNA tool
– Data Management – Data Analysis– Data Visualization– Comparision of tool use
Conclusions & Outlook TeLLNet project
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-4
CUELC
Social Network Analysis (SNA) [Freeman 1979, Wasserman and Faust 1994]
- Fundamentals of Graph Theory: Size, order, radius, diameter, distances- Bottom-up approach: Searching more complex structures- Structural aspects: Subgraphs, k-cliques, k-plexes, cut points, bridges, clus-
tering (coefficients), connectivity, cohesion- Special phenomena: Small-world effect, Pareto distribution- Centralities: Degree, Closeness and Betweenness centrality
Network Visualization [Brandes and Wagner 2004, Krempel 2005]
- The goal is to communicate complex information intuitively- Human perception sets limits to distinguish colors and shapes
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Social Network Analysis and Visualization
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-5
CUELC
Social Networks and Tools Most popular social networks realize only few analysis aspects
Analysis and visualization tools are not sufficient or too complexNetwork Workbench Visone [Brandes and Wagner 2004]
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-6
CUELC
eTwinning ScenarioeTwinning:• Founded in 2005 andcoordinated by theEuropean Schoolnet• Projects must be doneby two or more partnersfrom different countries• Internet platform withworkspaces and (com-munication) tools
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-7
CUELC
Data Management for the Case Study
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-8
CUELC
Data Preprocessing
8
Amount of available information:– 40450 schools, 45217 teachers, 8361 projects– not all attributes are required or should be aggregated– many data records contain uncertain or wrong information
A new relational database with tables for:– schools, teachers, projects and countries– affiliation between teachers – schools– affiliation between teachers/schools – projects
Schools Projects Teachers
0,01%
0,10%
1,00%
10,00%
100,00%45,12%
10,44%
0,08%0,05%
14,10%
46,15%
3,89%
0,01%
impossible numbers of pupilsimpossible agesunexpected valuesblank values
Noise in data records
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-9
CUELC
Statistical and Analytic Functions Statistical information from the database Already interpreted questions create networks on
demand, reduced to- “Answer-“nodes and all nodes
on shortest paths in-between- Direct neighbours- Edges are automatically deleted,
if end points are removed
SNA aspects can be applied to the current network
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-10
CUELC
Speed of growth The teacher network grows much more than the school network The country network is nearly completely connected
2005 2006 2007 20080
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
8616
9129
1848
45
1746 1814
110 0
Network growing by registration of schools
new nodes total edges2005 2006 2007 2008
0
2000
4000
6000
8000
10000
12000
14000
16000
9724
10945
13469
6411
2207 2560 2771
518
Network growing
by registration of teachers
new nodes total edges
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-11
CUELC
Visual Analytics, e.g. forthe Teacher Network of 2008
Labels and dates help to identify complete substructures
75 % of nodes are not connected
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-12
CUELC
Analysis of Subnetworks 22 complete substructures Largest component with 65 nodes, 213 edges Diameter 10, radius 5 12 cut points and 4 bridges Clustering coefficient 0,81
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-13
CUELC
Usage in the Evaluation Evaluation with
– German teachers who participate in eTwinning
– “Web Science” students from RWTH Aachen University
Teachers were– Fewer– But used the tool more
Positively rated Negatively rated
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-14
CUELC
Prior Knowledge and Handling
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-15
CUELC
Impressions ofVisualization and Statistics
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-16
CUELC
Knowledge and its Application
Teachers do not get it!
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-17
CUELC
Conclusions
SNA & visualization as tools for competencedevelopment for teachers in learning networks
eTwinning case study– Complex data management issues– Visual complexity of networks– Experimenting with web-based tools– Evaluation demonstrated
– Usefulness of the tool and the approach– Need for teacher training in theory and practice– Study effect of interventions by training
in the eTwinning database
Lehrstuhl Informatik 5(Informationssysteme)
Prof. Dr. M. JarkeI5-RK-0909-18
CUELC
Outlook: TeLLNet ProjectTeachers' Lifelong Learning Networks
Project within the EU Lifelong Learning Programme 3 years duration Project idea: Competence development for teachers in
learning networks with social network analysis and scenariobuilding based on eTwinning
Partners– European Schoolnet– Institute for Prospective Tecnological Studies (IPTS) –
Joint Research Centre of the European Comission– Open University of the Netherlands– RWTH Aachen University
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