Before going through an overview of the major machine learning techniques, let's go through the function that we would want to optimize in a regression technique or a classification technique.

# Overview of machine learning techniques

# Objective function in regression

In a regression exercise, we estimate the continuous variable value. In such a scenario, our predictions can be lower than the actual value or higher; that is, the error value could be either positive or negative. In such a scenario, the objective function translates to minimizing the sum of squared values of the difference between the actual and predicted values of each of the observations in the dataset.

In mathematical terms, the preceding is written as...