Quiz Question – Communities

2022-012

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To uncover the community structure of networks, we can use hierarchical clustering algorithms, and dendrograms help us to extract the underlying community organization. Analyze the figure below, observing the colored lines (A, B, and C) that cut the dendrogram to define communities.

Select the correct alternative:

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1. Line A (red) produces three communities: (c1): 6, 9, 13; (c2): 1, 8, 3, 14, 7, 2, 11, 15; (c3): 5, 16, 10, 4, 12, 17. 
2. Line B (green) produces six communities: (c1): 6, 9, 13; (c2): 1, 8; (c3):  3, 14, 7; (c4): 2, 11, 15; (c5): 5, 16, 10; (c6): 4, 12, 17.
3. Line C (brown) produces eleven communities: (c1): 6, 9, 13; (c2): 1; (c3): 8; (c4): 3; (c5): 14; (c6): 7; (c7): 2; (c8): 11; (c9): 15; (c10): 5, 16, 10; (c11): 4, 12, 17.
4. All statements are correct.
5. None of the above.

Original idea by: Rubens de Castro Pereira