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What is the difference between test set and validation set?

When conducting multiple regression, when should you center your predictor variables & when should you standardize them?

Why is Euclidean distance not a good metric in high dimensions?

Bagging, boosting and stacking in machine learning

What is batch size in neural network?

What does AUC stand for and what is it?

How would you explain covariance to someone who understands only the mean?

How would you explain Markov Chain Monte Carlo (MCMC) to a layperson?

How to know that your machine learning problem is hopeless?

What are the differences between Factor Analysis and Principal Component Analysis?

How to choose a predictive model after k-fold cross-validation?

Algorithms for automatic model selection

Intuitive explanation for dividing by $n-1$ when calculating standard deviation?

What does the hidden layer in a neural network compute?

How to deal with perfect separation in logistic regression?

Why do we need sigma-algebras to define probability spaces?

A list of cost functions used in neural networks, alongside applications

Deriving the conditional distributions of a multivariate normal distribution

What is the difference between a neural network and a deep neural network, and why do the deep ones work better?

How to reverse PCA and reconstruct original variables from several principal components?

Why L1 norm for sparse models

Obtaining knowledge from a random forest

Nested cross validation for model selection

Clustering on the output of t-SNE

Bias and variance in leave-one-out vs K-fold cross validation

How would you explain the difference between correlation and covariance?

Is it possible to have a pair of Gaussian random variables for which the joint distribution is not Gaussian?

Why does the Lasso provide Variable Selection?

What's a real-world example of "overfitting"?

Is it necessary to scale the target value in addition to scaling features for regression analysis?