Exploratory Social Network Analysis with Chapter 4: Sentiments & Friendship

2. LIKE DISLIKE
• Cohesion of Affection
• Attraction & Repulsion
• Factionalism

3. BALANCE THEORY: 1940S, FRITZ HEIDER, SOCIAL PSYCHOLOGIST
Person (P)-Other(O)-Topic(X) Triple
Unbalanced Balanced
Balancing:
• Adjusting Opinion on X
• Changing Affections for O
• Convincing O to X

4. SIGNED GRAPH
• D. Cartwright, Social Psychologist, & F. Harary, Mathematician
• Friendship, Like, Attraction  Positive ( + ) Weight Solid Arc
• Hostility, Dislike, Repulsion  Negative ( - ) Weight Dashed Arc
• Balanced [Directed] Signed Graph
• No [semi] cycle with uneven number of negative arc
• [semi] Cycle: Closed [semi] path, same start & end vertices
A signed graph is balanced if it can be partitioned into two clusters such that all
positive ties are contained within the clusters and all negative ties are situated
between the clusters

5. SIGNED GRAPH
Technique [Small Graph]:
Draws positive lines, which indicate attraction, as short as
possible and negative lines, which signal repulsion, as long as
possible, clusters of positive ties are clearly visible in a sociogram.

6. CLUSTERABILITY
• Generalize Balance Partitions to MORE than two
Davis proved that a network is clusterable if it contains no
semicycles with exactly one negative arc.
Clearly, balance is a special case of clusterability because all
balanced semicycles are clusterable

7. PAJEK
1.Create the initial partition
 Number of partitions determines the number of clusters.
 manually/randomly by Partition > Create Random Partition.
2. Invoking the Balancing Optimization Technique
 Repetition number
 Alpha as the coefficient for error calculation
 Network > Signed Network > Create Partition > Doreian-Mrvarmethod*
Optimization Technique:
• Several Solutions
• Does not Find the Best Fitting Clustering
• Starting Options may Yield Different Results

8. PAJEK
Forbidden Arcs  Error :
Maximally Balanced  Minimized Error

9. LONGITUDINAL ANALYSIS
Error Evaluation of Network in Different Time Points