Quiz on Unsupervised Learning and Clustering

What is the primary goal of clustering in unsupervised learning?

• To reduce dimensionality of data

• To classify data into predefined categories

• To find natural groupings in data

• To predict future outcomes

Which of the following is a type of hierarchical clustering?

• K-means clustering

• Agglomerative clustering

• DBSCAN

• Fuzzy C-Means

What does the K in K-means represent?

• The number of features

• The number of clusters

• The number of iterations

• The number of data points

Which clustering algorithm allows for overlapping clusters?

• Agglomerative clustering

• DBSCAN

• K-means

• Fuzzy C-Means

What is the main disadvantage of K-means clustering?

• It can only form spherical clusters

• It cannot handle noise

• It requires the number of clusters to be specified in advance

• It is computationally expensive

What does DBSCAN stand for?

• Density-Based Spatial Clustering of Applications with Noise

• Density-Based Statistical Clustering of Applications with Noise

• Dynamic-Based Statistical Clustering of Applications with Noise

• Dynamic-Based Spatial Clustering of Applications with Noise

Which method is used to determine the optimal number of clusters in K-means?

• Silhouette analysis

• Elbow method

• Dendrogram analysis

• Variance analysis

In K-means clustering, what is the purpose of the centroid?

• To represent the average of all points in a cluster

• To determine the number of clusters

• To serve as the initial point for clustering

• To represent the most distant point in a cluster

What is a key feature of fuzzy C-Means clustering?

• Each sample belongs to exactly one cluster

• It requires the number of clusters to be specified in advance

• Clusters are always spherical

• Samples can belong to multiple clusters with varying degrees

What is the main advantage of hierarchical clustering?

• It is faster than K-means

• It is less sensitive to noise

• It does not require specifying the number of clusters upfront

• It can only form spherical clusters