12.6 Clustering

Learning objectives

• Two best-known clustering approaches: K-means clustering and hierarchical clustering

• Discuss clustering observations on the basis of the features

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Questions

What it means for two or more observations to be similar or different?

What is the difference between PCA and Clustering?

• PCA looks to find a low-dimensional representation of the observations that explain a good fraction of the variance;
• Clustering looks to find homogeneous subgroups among the observations.

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