## What is the shape of K-means clustering?

spherical shapes

Kmeans assumes spherical shapes of clusters (with radius equal to the distance between the centroid and the furthest data point) and doesn’t work well when clusters are in different shapes such as elliptical clusters.

## Do you need to scale for K-means clustering?

Hence, it is always advisable to bring all the features to the same scale for applying distance based algorithms like KNN or K-Means.

**How would you determine the size of K in K-means clustering?**

The Elbow Method Calculate the Within-Cluster-Sum of Squared Errors (WSS) for different values of k, and choose the k for which WSS becomes first starts to diminish. In the plot of WSS-versus-k, this is visible as an elbow. Within-Cluster-Sum of Squared Errors sounds a bit complex.

### Is scaling necessary for hierarchical clustering?

It depends on the type of data you have. For some types of well defined data, there may be no need to scale and center. A good example is geolocation data (longitudes and latitudes). If you were seeking to cluster towns, you wouldn’t need to scale and center their locations.

### How is K-means performance measured?

You can evaluate the performance of k-means by convergence rate and by the sum of squared error(SSE), making the comparison among SSE. It is similar to sums of inertia moments of clusters.

**On what basis does K-means clustering define clusters?**

A cluster refers to a collection of data points aggregated together because of certain similarities. You’ll define a target number k, which refers to the number of centroids you need in the dataset. A centroid is the imaginary or real location representing the center of the cluster.

#### What is K-means clustering in machine learning?

k-means is a technique for data clustering that may be used for unsupervised machine learning. It is capable of classifying unlabeled data into a predetermined number of clusters based on similarities (k).

#### What is true about k-means clustering?

K-Means Clustering is an unsupervised learning algorithm that is used to solve the clustering problems in machine learning or data science. In this topic, we will learn what is K-means clustering algorithm, how the algorithm works, along with the Python implementation of k-means clustering.

**What is a centroid point in k-means clustering?**

A centroid is the imaginary or real location representing the center of the cluster. Every data point is allocated to each of the clusters through reducing the in-cluster sum of squares.