Data Science Deep Learning and Neural Networks

Question 1

What is the primary role of an activation function in a neural network?

Accepted Answer

To introduce non-linearity into the model

Answer

Activation functions introduce non-linearity, allowing neural networks to learn complex patterns beyond simple linear relationships.

Question 2

Which optimization algorithm adapts the learning rate for each parameter using estimates of first and second moments of the gradients?

Accepted Answer

Adam

Answer

Adam (Adaptive Moment Estimation) combines momentum and RMSProp by tracking both the first and second moments of gradients.

Question 3

What does the term 'epoch' mean in the context of training a neural network?

Accepted Answer

One complete pass through the entire training dataset

Answer

An epoch is one full pass through all training examples, after which weights have been updated based on every sample.

Question 4

Which technique randomly drops neurons during training to reduce overfitting in neural networks?

Accepted Answer

Dropout

Answer

Dropout randomly sets a fraction of neuron outputs to zero during each training step, forcing the network to learn redundant representations.

Question 5

In a convolutional neural network (CNN), what does a pooling layer primarily do?

Accepted Answer

Reduces spatial dimensions of feature maps

Answer

Pooling layers downsample feature maps by summarizing regions, reducing computation and providing translation invariance.

Data Science Practice Test