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How Social Network Analysis can help to measure cohesion in collaborative distance-learning. Christophe REFFAY Thierry CHANIER Laboratoire d’Informatique de Franche-Comté Besançon - France. Outline. Introduction Experiment : Simuligne learning session SNA computational models Cliques - PowerPoint PPT Presentation
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1
FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
How Social Network Analysis
can help to
measure cohesion in collaborative distance-learning
Christophe REFFAYThierry CHANIER
Laboratoire d’Informatique de Franche-Comté Besançon - France
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Outline
1. Introduction
2. Experiment : Simuligne learning session
3. SNA computational models
– Cliques
– Clusters
4. Conclusion
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
The problem
Distance:
Interaction data
Face-to-face:
Visual & Oral indices
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Our approach:
Hypothesis
• CL works well in « Active » groups.
• Collaboration requires communication
Questions• synthesis from
communication data • appropriateness• importance • computability
• Representation
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
How SNA can help ?
Social Network Analysis, based on:
• Group dynamics
• Social relationships models
• Graph theory
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
The central role of "Cohesion"
• Necessary for collaborative tasks
• Very important for social aspects
• Essential for motivation (no isolation)
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Cohesion ?
much more complex than… temperature, speed, or weight…
…Less physical, and more human !
Cohesion is an attractive "force" between individuals
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Cohesive subgroups
SNA (Wasserman & Faust, 1994) :
"Subsets of actors among whom there are relatively
strong, direct, intense, frequent or positive ties"
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Experiment : "Simuligne": distance learning course
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Research context : the ICOGAD project
Laboratoire dePsychologie de Nancy
(France)
partner
Laboratoire d'Informatiquede Franche-Comté
(France)
leader
Department ofLanguages - Open
University (UK)
partner
Programme COGNITIQUE 2000
Research Ministry of France
(53 K€)
Simuligne : The training session
ICOGAD Project
Analysis of interaction tracks from SimuLigne
Definition of needed indicators to follow a group
Development of new tools to plug in LMS
Simuligne : The training session
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Pedagogical hypothesis
To produce together
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
The learning context
• 100% at a distance• French as foreign language• Public : 40 adults
– English speakers– Advanced level in French– Web litterate
• Groups of 10 + tutor + 2 NS• LMS : WebCT• 30 hours over 10 weeks
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
The Simuligne organisationCoordinator
Aquitania Gallia Lugdunensis Narbonensis
Learners Learners Learners Learners
Tutor Tutor Tutor Tutor
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Simuligne Interaction data
• e-mail : 834 753 chars in 4 062 messages
• Forum : 879 015 chars in 2 686 messages
• Chat : 234 694 char. in 5 680 speach turns
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Communication graphs
• Only read (opened) messages.
• (separately) on E-mail or Forum
• for a given period
• Gives the number of messages sent by A
and read by B on the directed edge A->B
Gallia E-mails over the whole training period
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
The E-mail Graph matrix
For Gallia over the whole training period
E-mails Gallia (without the tutor)
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
A forum graph (Gallia)
… Not very useful information
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Forum Matrix
Gt Gl1 Gl2 Gn1 Gl3 Gl4 Gl5 Gn2 Gl6 Gl9 Gl10Gt 107 107 99 106 90 107 26 106 107 25 27Gl1 60 60 52 59 45 60 7 59 60 11 9Gl2 27 27 27 24 24 27 5 25 27 3 4Gn1 36 36 33 36 29 36 6 36 36 5 7Gl3 18 18 18 18 15 18 1 18 18 3 1Gl4 48 48 42 47 38 48 8 47 48 9 8Gl5 7 7 6 7 4 7 5 7 7 4 6Gn2 30 30 27 28 25 30 5 28 30 4 5Gl6 14 15 14 14 11 15 3 14 15 3 3Gl9 9 9 7 9 6 9 5 9 9 5 7Gl10 5 5 3 5 4 5 3 5 5 2 2
Not straightforward to use...
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Our first try…
Global index of cohesion (Group)– 0 for no relation– Based on shared neighbours– 1 for a fully connected graph
• Number of messages ignored• Difficult to define evolution • No information on individuals
But:
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Def. : A clique of level c is a set where all members are directly connected one to another with a value c.
Clique of level c (valued graph)
Clique of level 10
15
10
13 12
101111
8
8
12
C = 10
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Computing cliques of level-c
• Symetrisation of the adjaccency matrix
• Definition of the threshold (c)
• Selection of ties >= c=10Gn1Gn2
Gt
Gl10
Gl6
Gl4
Gl2
Gl1
7
512
1432
10
10
7 8
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Computing cliques of level-c
Each pair of members of the resulting subset exchanged at least 10 messages. Gn1Gn2
Gt
Gl10
Gl6
Gl4
Gl2
Gl1This is a cohesive subset
Property:
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Result on Gallia for c=10
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Comparing the 4 groups
Aquitania
Gallia
Lugdunensis
Gallia
Narbonensis
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Information given by Cliques
• A good picture of the group structure
• Highlights cohesive groups
• Highlights isolated individuals
… for a given threashold c !
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Hierarchical Clusters
Initially : identity partition : N clusters
Repeat
Find the most communicant pair of clusters
Fusion of the pair in one cluster
Print communication level (k)
N = N-1
Until (N=1)
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Hierarchical Clusters for GalliaGALLIA G G G G G G G G G G l l l n l G l n l l l 1Level 3 2 1 1 t 4 2 6 5 9 0----- - - - - - - - - - - - 167 . . . XXX . . . . . . 108 . . . XXXXX . . . . . 83 . . XXXXXXX . . . . . 64 . . XXXXXXXXX . . . . 52 . XXXXXXXXXXX . . . . 42 XXXXXXXXXXXXX . . . . 29 XXXXXXXXXXXXXXX . . . 9 XXXXXXXXXXXXXXX XXXXX
5 XXXXXXXXXXXXXXXXXXXXX
Max
Min
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Discussion
• Cliques of level c gives:– precise communication structure (for a given c).– cohesive subsets – isolated individuals.
• Clusters:– show more about intensity – Easier to compare groups.
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Technical Conclusion
• Cliques and clusters: complementary information
• Process1. Clusters analysis on all groups
2. Then threshold c
3. Level-c cliques
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Further work
• User friendly representations
– Development
– Experiment
• SNA multiplexity: integration of all com
tools into one representation
• Exploration of SNA models
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Questions ?
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CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
From data to social indices
• LMS data extraction
• relationship definitions (graphs)
• Apropriate model
• User friendly representation
E-mails of Aquitania during the whole training period
Aquitania (without the tutor)
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
(questions) Activity as a whole
• A LMS is an integration of many tools• The designer can use them differently :
– Communication (Forum, e-mail, Chat, …)
– Production (texts, drawing, cards, etc…)
– Tests (quizzes, auto-evaluation,…)
– Reading, contents pages navigation, etc.
• One learner can participate to many courses• To reckon cohesion only on forum is not sufficient
in general, but a good starting point in “simuligne”
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
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FRE 2661
CSCL Conference, Bergen, june 2003C. Reffay, T. Chanier
Using the Cliques of level c
Gn1Gn2
Gt
Gl10
Gl6
Gl5 Gl9
Gl4
Gl3
Gl2
Gl1 C=10