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Faith Cheptoo
Faith Cheptoo

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Unsupervised Learning: Clustering

Discovering hidden patterns

Ever wondered how Spotify suggests playlists you didn't even know you would like? Or how online stores group similar products for you? That is where unsupervised learning comes in, and specifically, clustering.

What is Unsupervised Learning?

Unlike supervised learning, where a model is trained with labeled data, unsupervised learning works without labels. It analyses the data and tries to find patterns or structures on its own. Think of it like walking into a library for the first time. You notice some books are on the same shelf because of their topic, even if no one tells you.

How Clustering Works

Clustering is a method for grouping data points that are similar to one another.
It is like having a basket of fruits: apples, oranges, and bananas. Without being told the categories, you might sort them by color or size. Clustering algorithms perform a similar function with data, automatically identifying groups that share common characteristics.

Popular Clustering Models

Some common clustering techniques include:

  • K-Means: Divides data into a set number of clusters. Simple but effective.
  • DBSCAN (Density-based spatial clustering of applications with noise): Detects clusters of any shape and identifies outliers. Great for messy data.
  • Hierarchical Clustering: Builds a tree of clusters, which can be useful for understanding relationships.

K-Means

I first tried clustering on a dataset of students using an AI assistant and realized the choice of clusters mattered a lot. At first, the groups didn’t make sense, but after tuning parameters and visualizing the data, I uncovered meaningful patterns. Some students clustered together because they interacted heavily with prompts, while others barely used the system. Finally, I discovered patterns that were not obvious at first glance.

Why Clustering Matters

Clustering can reveal hidden insights, guide decision-making, and even improve user experiences. Whether it’s grouping customers, students, or products, the ability to find structure in unlabeled data is incredibly powerful.

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