What Does Silhouette Score Tell Us?

The Silhouette score is a metric used in machine learning to measure the quality of a clustering algorithm. It is based on the idea that points within a cluster should be similar to each other, and points in different clusters should be different.

The Silhouette score measures how well this idea is achieved by calculating the distance between each point and its closest cluster, and then comparing it to the distance between each point and its second closest cluster. The higher the score, the better the clustering algorithm.

The Silhouette score is calculated as follows: for each point, calculate the average distance to all other points in its own cluster (the “intracluster” distance). Do this for all points in all clusters.

Then calculate the average distance between each point and all points in other clusters (the “intercluster” distance). Finally, subtract the intracluster average from the intercluster average for each point, giving you a score from -1 to 1.

A perfect score of 1 means that every point is exactly where it should be; it’s far away from any other clusters but close to its own. A score of 0 means that there’s no clear pattern; some points may be close to their own cluster but also close to another. And finally, a score of -1 means that everything has gone wrong; all points are equally far away from any other clusters.

What Does Silhouette Score Tell Us?

The Silhouette score provides an indication of how well-separated our data is into distinct clusters. It can help us judge how good our clustering model is performing at grouping related data together while keeping unrelated data apart. In addition, it can also help us identify if our model has overfitted or underfitted our data.

Conclusion:
The Silhouette score gives us an insight into how well our machine learning clustering algorithms are doing at separating our data into distinct groups. It helps us understand if we have overfit or underfit our model by measuring how close or far apart individual points are from their closest cluster versus their second closest cluster.