ML 4 Classification Quiz

What is the primary function of the KNN algorithm?

• Regression analysis

• Classification and regression

• Dimensionality reduction

• Clustering

What does the K in KNN stand for?

• Knowledge

• Kernel

• K-means

• Number of Neighbors

Which metric is used by KNN to classify a new data point?

• Manhattan distance

• Cosine similarity

• Euclidean distance

• Jaccard index

What is a key limitation of KNN?

• It cannot handle numerical data

• It is not interpretable

• It becomes slow with large datasets

• It requires labeled data

Which of the following is true about a Decision Tree?

• It always results in linear models

• It splits data based on information gain or Gini index

• It uses distance-based classification

• It clusters data points

How does a Random Forest improve over a single Decision Tree?

• By pruning branches

• By using distance measures

• By combining multiple trees for better accuracy

• By reducing input features

What does a Confusion Matrix represent?

• Clustering output

• Accuracy plot

• Summary of prediction results

• Loss function values

Which value in a confusion matrix shows the number of incorrectly predicted positive instances?

• True Positive

• False Positive

• False Negative

• True Negative

What does 'Precision' measure in classification?

• Correctly predicted positives out of all predicted positives

• All positives in dataset

• Overall model accuracy

• True positives out of actual positives

How is Recall calculated?

• TP / (TP + FP)

• TP / (TP + FN)

• TN / (TN + FP)

• FP / (FP + TN)