Tools to crack your data science Interviews
Recap: Skip-Gram model is a popular algorithm to train word embeddings such as word2vec. It tries to represent each word in a large text as a lower dimensional vector in a space of K dimensions such that similar words are closer to each other. This is achieved by training a feed-forward network where we try…
This is an example of Named Entity Recognition(NER) problem. One can build a sequence model such as an LSTM to perform this task. However, as shown in both the sentences above, forward only LSTM might fail here. Using forward only direction LSTM might result in a model which recognises Teddy as a product : “bear”, which is on…
Language models can be built using the following popular methods – Using n-gram language model n-gram language models make assumption for the value of n. Larger the value of n, longer the dependency. One can refer to what is the significance of n-grams in a language model for further reading. Using hidden Markov Model(HMM) HMM maintains long…
Gradient descent is the most commonly used training algorithm. Momentum is a common way to augment gradient descent such that gradient in each step is accumulated over past steps to enable the algorithm to proceed in a smoother fashion towards the minimum. RMS prop attempts to adjust learning rate for each iteration in an automated…
The batch size is a hyper parameter. Usually people try various values to see what works best in terms of speed and accuracy. Suppose you have M training instances and k batches, higher batch size is faster to do a pass on the entire dataset, through M/k mini batch iterations. As long as the data…
Ans. The commonly used loss functions are Linear : g(x) = x. This is the simplest activation function. However it cannot model complex decision boundaries. A deep network with linear activations can be shown incapable of handling non-linear decision boundaries. Sigmoid : This is a common activation function in the last layer of the neural…
Increase the number of training iterations Make a more complex network – increase hidden layer size Initialize weights to a random small value instead of zeros Change tanh activations to relu Ans : (3) . I will initialize weights to a non zero value since changing all the weights in the same…
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…
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…
High bias means the data is being underfit. The decision boundary is not usually complex enough. High variance happens due to over fitting, the decision boundary is more complex than what it should be. High bias high variance happens when you fit a complex decision boundary that is also not fitting the training set…