Questions

1. What's the difference between agglomerative and divisive approaches?
2. Given two clusters a: [(-1, -1), (0, 0)] and b: [(1, 1), (1, 0)], what are the single and complete linkages considering the Euclidean distance?
3. A dendrogram represents the different linkage results for a given dataset. Is this correct?
4. In agglomerative clustering, the bottom (initial part) of a dendrogram contains a single cluster. Is this correct?
5. What's the meaning of the y axis of a dendrogram in agglomerative clustering?
6. The dissimilarity decreases while merging smaller clusters. Is this correct?
7. An element, C(i, j), of the cophenetic matrix reports the dissimilarity level at which two corresponding elements, x_i and x_j, appear in the same cluster for the first time. Is this correct?
8. What's the main purpose of connectivity constraints?

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