round2,flashcard-1

Front

Which technique is used to reduce the number of features in a dataset while retaining important information?

Back

Principal Component Analysis (PCA)

Front

What is the purpose of a confusion matrix in classification problems?

Back

The purpose of a confusion matrix is to evaluate the performance of a classification model.

Front

Which of the following is NOT a type of machine learning? A) Supervised Learning, B) Unsupervised Learning, C) Reinforcement Learning, D) Data Mining

Back

Data Mining

Front

Which metric is best suited for evaluating imbalanced classification problems?

Back

F1-score

Front

What is the main advantage of using a Random Forest over a single Decision Tree?

Back

Random Forest reduces overfitting.

Front

Which of the following ensures data integrity in a blockchain? Options:

• A) Hashing

,

• B) Smart Contracts

,

• C) Public Key Encryption

,

• D) Digital Wallets

Back

Hashing

Front

Which consensus algorithm is primarily used in Bitcoin?

Back

Proof of Work (PoW)

Front

What is a smart contract in blockchain?

Back

A self-executing contract with predefined rules

Front

What is the purpose of gas fees in Ethereum transactions?

Back

To pay miners for validating transactions

Front

Which type of blockchain allows only selected participants to validate transactions?

Back

Private Blockchain