## What is the Difference Between a Batch and an Epoch in a Neural Network?

Stochastic gradient descent is a learning algorithm that has a number of hyperparameters. Two hyperparameters that often confuse beginners are the batch size and number of epochs. They are both integer values and seem to do the same thing. In this post, you will discover…

## The Role of Randomization to Address Confounding Variables in Machine Learning

A large part of applied machine learning is about running controlled experiments to discover what algorithm or algorithm configuration to use on a predictive modeling problem. A challenge is that there are aspects of the problem and the algorithm called confounding variables that cannot be…

## All of Statistics for Machine Learning

A foundation in statistics is required to be effective as a machine learning practitioner. The book “All of Statistics” was written specifically to provide a foundation in probability and statistics for computer science undergraduates that may have an interest in data mining and machine learning….

## A Gentle Introduction to Statistical Power and Power Analysis in Python

The statistical power of a hypothesis test is the probability of detecting an effect, if there is a true effect present to detect. Power can be calculated and reported for a completed experiment to comment on the confidence one might have in the conclusions drawn…

## A Gentle Introduction to Effect Size Measures in Python

Statistical hypothesis tests report on the likelihood of the observed results given an assumption, such as no association between variables or no difference between groups. Hypothesis tests do not comment on the size of the effect if the association or difference is statistically significant. This…

## How to Calculate Nonparametric Rank Correlation in Python

Correlation is a measure of the association between two variables. It is easy to calculate and interpret when both variables have a well understood Gaussian distribution. When we do not know the distribution of the variables, we must use nonparametric rank correlation methods. In this…

## How to Generate Random Numbers in Python

The use of randomness is an important part of the configuration and evaluation of machine learning algorithms. From the random initialization of weights in an artificial neural network, to the splitting of data into random train and test sets, to the random shuffling of a…

## Statistics for Evaluating Machine Learning Models

Tom Mitchell’s classic 1997 book “Machine Learning” provides a chapter dedicated to statistical methods for evaluating machine learning models. Statistics provides an important set of tools used at each step of a machine learning project. A practitioner cannot effectively evaluate the skill of a machine…

## The Close Relationship Between Applied Statistics and Machine Learning

The machine learning practitioner has a tradition of algorithms and a pragmatic focus on results and model skill above other concerns such as model interpretability. Statisticians work on much the same type of modeling problems under the names of applied statistics and statistical learning. Coming…