Book Image

Machine Learning Solutions

Book Image

Machine Learning Solutions

Overview of this book

Machine learning (ML) helps you find hidden insights from your data without the need for explicit programming. This book is your key to solving any kind of ML problem you might come across in your job. You’ll encounter a set of simple to complex problems while building ML models, and you'll not only resolve these problems, but you’ll also learn how to build projects based on each problem, with a practical approach and easy-to-follow examples. The book includes a wide range of applications: from analytics and NLP, to computer vision domains. Some of the applications you will be working on include stock price prediction, a recommendation engine, building a chat-bot, a facial expression recognition system, and many more. The problem examples we cover include identifying the right algorithm for your dataset and use cases, creating and labeling datasets, getting enough clean data to carry out processing, identifying outliers, overftting datasets, hyperparameter tuning, and more. Here, you'll also learn to make more timely and accurate predictions. In addition, you'll deal with more advanced use cases, such as building a gaming bot, building an extractive summarization tool for medical documents, and you'll also tackle the problems faced while building an ML model. By the end of this book, you'll be able to fine-tune your models as per your needs to deliver maximum productivity.
Table of Contents (19 chapters)
Machine Learning Solutions
Foreword
Contributors
Preface
Index

Testing the revised approach


In this section, we will perform testing of the revised approach. Before performing actual testing and seeing how good or bad the chatbot conversation is, we need to understand the basic testing metrics that we will be using for this approach and for the best approach. These testing metrics help us evaluate the model accuracy. Let's understand the testing metrics first, and then we will move on to the testing of the revised approach.

Understanding the testing metrics

In this section, we need to understand the following testing metrics:

  • Perplexity

  • Loss

Perplexity

In the NLP domain, perplexity is also referred to as per-word perplexity. Perplexity is a measurement of how well a trained model predicts the output for unseen data. It is also used to compare probability models. A low perplexity indicates that the probability distribution is good at predicting the sample. Even during training, you can see that for each checkpoint, perplexity is decreasing. Ideally, when there...