Two-mode networks Kaibin He
Two-mode networks
Kaibin He
Outline
• Data structure• Visualization• Quantitative Analysis• Qualitative Analysis
Rectangular data array
1 2 3
A 0 1 0
B 1 0 1
1 2 3
A 0 1 0
B 1 2 1
Two-mode to One-mode• Data>Affiliations
• Cross-product(binary data) : multiplies each of A's scores by the corresponding score for B, and then sums across the columns
1 2 3
A 0 1 0
B 1 0 1
1 2 31 1 0 1
2 0 1 0
3 1 0 1
A B
1 0 1
2 1 0
3 0 1
Two-mode to One-mode
• Minimums (valued data): examines the entries of A and B for campaign 1, and selects the lowest score (zero). It then does this for the other campaigns and sums.
1 2 31 1 1 1
2 1 3 1
3 1 1 1
1 2 3
A 0 1 0
B 1 2 1
A B
1 0 1
2 1 2
3 0 1
Bipartite
• The matrix is formed by adding the rows as additional columns, and columns as additional rows. Transform>Bipartite
1 2 3
A 0 1 0
B 1 0 1
A B 1 2 3
A 0 0 0 1 0
B 0 0 1 0 1
1 0 0 0 0 0
2 0 0 0 0 0
3 0 0 0 0 0
Visualization
• Netdraw>File>UCINET dataset>2-Mode Network
• Use scaling method to locate the points
• Example: Zhou, Yuan, Wang (2013)
Quantitative analysis
• Identify underlying dimensions of the joint space of actor-by-event.
• Two-mode SVD analysis. (valued data)Tools>Scaling/Decomposition>SVD
• Two-mode factor analysis. (valued data)Tools>Scaling/Decomposition>Factor Analysis
• Two-mode correspondence analysis. (binary data)Tools>Scaling/Decomposition>Correspondence
SVD
• Singular Values• RCScores• Row Scores• Column Scores• Scatter Plot
• Example
Factor Analysis
• Eigenvalues• Loadings• Scatter plot
• Example
Correspondence analysis
• Row/Column Scores• Scatter plot
• Example
Qualitative analysis
• Block models
• Two-mode core-periphery analysis. Network>2-Mode>Categorical Core>Periphery
• Two-mode factions analysis Network>2-Mode>2-Mode Factions
Two-mode core-periphery analysis
• The "core" is a cluster of frequently co-occurring actors and events.
• The "periphery" consists of a partition of actors who are not co-incident to the same events.
• 0 means bad fit, 1 means excellent fit.• Ideal density matrix
1 2
1 1
2 0
Two-mode factions analysis
• Factions are groupings that have high density within the group, and low density of ties between groups.
• Example
Recommended paper
The Quest for Content: How User-GeneratedLinks Can Facilitate Online Exploration
JACOB GOLDENBERG, GAL OESTREICHER-SINGER, and SHACHAR REICHMAN JMR, 2012
• Is social network important to e-business?
product pages linked by hyperlinks & user generated links
conclusion
This dual-network structure in facilitating content exploration.