Plotting WCSS against the number of clusters is used to identify the elbow; what is the method commonly referred to as?

Plotting WCSS against the number of clusters is used to identify the elbow; what is the method commonly referred to as?

• A. Dendrogram
• B. Silhouette Scores
• C. Scree Plots (Elbow Method)
• D. BCSS Plot

Answer: (C)

When you’re deciding how many clusters to use, you look at how tightly data points fit inside their clusters as you increase the number of clusters. Within-cluster sum of squares (WCSS) tends to drop as k grows, because more clusters can fit the data more closely. But after a certain point, adding another cluster doesn’t appreciably improve the fit—the curve bends and flattens. The spot where that bend occurs is the elbow, signaling a good balance between simplicity and fit. This visualization is commonly referred to as the elbow method, and it’s often presented as a Scree Plot, which is why the option named Scree Plots (Elbow Method) is the best fit. Dendrograms relate to hierarchical clustering, silhouette scores measure cluster separation without relying on WCSS elbow plots, and BCSS plots depict between-cluster dispersion, not the WCSS elbow approach.

When you’re deciding how many clusters to use, you look at how tightly data points fit inside their clusters as you increase the number of clusters. Within-cluster sum of squares (WCSS) tends to drop as k grows, because more clusters can fit the data more closely. But after a certain point, adding another cluster doesn’t appreciably improve the fit—the curve bends and flattens. The spot where that bend occurs is the elbow, signaling a good balance between simplicity and fit. This visualization is commonly referred to as the elbow method, and it’s often presented as a Scree Plot, which is why the option named Scree Plots (Elbow Method) is the best fit. Dendrograms relate to hierarchical clustering, silhouette scores measure cluster separation without relying on WCSS elbow plots, and BCSS plots depict between-cluster dispersion, not the WCSS elbow approach.