Book Image

The Data Science Workshop

By : Anthony So, Thomas V. Joseph, Robert Thas John, Andrew Worsley, Dr. Samuel Asare
Book Image

The Data Science Workshop

By: Anthony So, Thomas V. Joseph, Robert Thas John, Andrew Worsley, Dr. Samuel Asare

Overview of this book

You already know you want to learn data science, and a smarter way to learn data science is to learn by doing. The Data Science Workshop focuses on building up your practical skills so that you can understand how to develop simple machine learning models in Python or even build an advanced model for detecting potential bank frauds with effective modern data science. You'll learn from real examples that lead to real results. Throughout The Data Science Workshop, you'll take an engaging step-by-step approach to understanding data science. You won't have to sit through any unnecessary theory. If you're short on time you can jump into a single exercise each day or spend an entire weekend training a model using sci-kit learn. It's your choice. Learning on your terms, you'll build up and reinforce key skills in a way that feels rewarding. Every physical print copy of The Data Science Workshop unlocks access to the interactive edition. With videos detailing all exercises and activities, you'll always have a guided solution. You can also benchmark yourself against assessments, track progress, and receive content updates. You'll even earn a secure credential that you can share and verify online upon completion. It's a premium learning experience that's included with your printed copy. To redeem, follow the instructions located at the start of your data science book. Fast-paced and direct, The Data Science Workshop is the ideal companion for data science beginners. You'll learn about machine learning algorithms like a data scientist, learning along the way. This process means that you'll find that your new skills stick, embedded as best practice. A solid foundation for the years ahead.
Table of Contents (18 chapters)


A model is said to overfit the training data when it generates a hypothesis that accounts for every example. What this means is that it correctly predicts the outcome of every example. The problem with this scenario is that the model equation becomes extremely complex, and such models have been observed to be incapable of correctly predicting new observations.

Overfitting occurs when a model has been over-engineered. Two of the ways in which this could occur are:

  • The model is trained on too many features.
  • The model is trained for too long.

We'll discuss each of these two points in the following sections.

Training on Too Many Features

When a model trains on too many features, the hypothesis becomes extremely complicated. Consider a case in which you have one column of features and you need to generate a hypothesis. This would be a simple linear equation, as shown here:

Figure 7.1: Equation for a hypothesis for a line...