Data Science FREE Data Science Unsupervised Learning Techniques Questions and Answers 2

Question 1

Which unsupervised learning method groups data points by iteratively assigning them to the nearest centroid and updating centroids until convergence?

Accepted Answer

K-Means Clustering

Answer

Principal Component Analysis

Answer

Apriori Algorithm

Answer

Isolation Forest

Question 2

What is the primary purpose of the elbow method in unsupervised learning?

Accepted Answer

Determining the optimal number of clusters

Answer

Selecting the best features for dimensionality reduction

Answer

Evaluating the accuracy of an anomaly detector

Answer

Choosing the learning rate for autoencoders

Question 3

In DBSCAN, what happens to data points that are neither core points nor reachable from any core point?

Accepted Answer

They are labeled as noise

Answer

They form their own cluster

Answer

They are assigned to the nearest cluster

Answer

They are removed from the dataset

Question 4

Which technique reduces dimensionality by finding a lower-dimensional manifold that preserves local neighbor distances?

Accepted Answer

t-SNE

Answer

K-Means

Answer

Agglomerative Clustering

Answer

Association Rule Mining

Question 5

What does the silhouette score measure in cluster analysis?

Accepted Answer

How similar a point is to its own cluster compared to the nearest neighboring cluster

Answer

The total variance explained by the clustering

Answer

The number of outliers detected in the dataset

Answer

The computational complexity of the clustering algorithm

Question 6

Which unsupervised technique is used to discover frequent itemsets and generate rules such as 'customers who buy bread often buy butter'?

Accepted Answer

Association Rule Mining

Answer

Gaussian Mixture Models

Answer

Hierarchical Clustering

Answer

Self-Organizing Maps