Whether you are kickstarting your interview preparation, or wrapping up your preparation and are looking for final touches, here are over 50 must see questions to prepare for a data science interview. We have put them in five categories for convenience. (Note: There are sevaral more questions along with answers in the main menu “Interview…

# Tag: deep learning

## What is the difference between deep learning and machine learning?

Deep learning is a subset of Machine Learning. Machine learning is the ability to build “models” that can learn automatically from data, without programming explicit rules. Machine Learning models typically have the ability to generalize to new data. Deep Learning is a field in machine learning where we build multi-layered artificial neural network models to…

## Suppose you build word vectors (embeddings) with each word vector having dimensions as the vocabulary size(V) and feature values as pPMI between corresponding words: What are the problems with this approach and how can you resolve them ?

Problems As the vocabulary size (V) is large, these vectors will be large in size. They will be sparse as a word may not have co-occurred with all possible words. Resolution Dimensionality Reduction using approaches like Singular Value Decomposition (SVD) of the term document matrix to get a K dimensional approximation. Other Matrix factorisation techniques…

## What are the different ways of preventing over-fitting in a deep neural network ? Explain the intuition behind each

L2 norm regularization : Make the weights closer to zero prevent overfitting. L1 Norm regularization : Make the weights closer to zero and also induce sparsity in weights. Less common form of regularization Dropout regularization : Ensure some of the hidden units are dropped out at random to ensure the network does not overfit by…

## I have designed a 2 layered deep neural network for a classifier with 2 units in the hidden layer. I use linear activation functions with a sigmoid at the final layer. I use a data visualization tool and see that the decision boundary is in the shape of a sine curve. I have tried to train with 200 data points with known class labels and see that the training error is too high. What do I do ?

Increase number of units in the hidden layer Increase number of hidden layers Increase data set size Change activation function to tanh Try all of the above The answer is d. When I use a linear activation function, the deep neural network is realizing a linear combination of linear functions which leads to modeling only…