Book Image

Modern Time Series Forecasting with Python

By : Manu Joseph
5 (1)
Book Image

Modern Time Series Forecasting with Python

5 (1)
By: Manu Joseph

Overview of this book

We live in a serendipitous era where the explosion in the quantum of data collected and a renewed interest in data-driven techniques such as machine learning (ML), has changed the landscape of analytics, and with it, time series forecasting. This book, filled with industry-tested tips and tricks, takes you beyond commonly used classical statistical methods such as ARIMA and introduces to you the latest techniques from the world of ML. This is a comprehensive guide to analyzing, visualizing, and creating state-of-the-art forecasting systems, complete with common topics such as ML and deep learning (DL) as well as rarely touched-upon topics such as global forecasting models, cross-validation strategies, and forecast metrics. You’ll begin by exploring the basics of data handling, data visualization, and classical statistical methods before moving on to ML and DL models for time series forecasting. This book takes you on a hands-on journey in which you’ll develop state-of-the-art ML (linear regression to gradient-boosted trees) and DL (feed-forward neural networks, LSTMs, and transformers) models on a real-world dataset along with exploring practical topics such as interpretability. By the end of this book, you’ll be able to build world-class time series forecasting systems and tackle problems in the real world.
Table of Contents (26 chapters)
1
Part 1 – Getting Familiar with Time Series
6
Part 2 – Machine Learning for Time Series
13
Part 3 – Deep Learning for Time Series
20
Part 4 – Mechanics of Forecasting

Long short-term memory (LSTM) networks

Hochreiter and Schmidhuber proposed a modification of the classical RNNs in 1997 – LSTM networks. It aimed to resolve the vanishing and exploding gradients in vanilla RNNs. The design of the LSTM was inspired by the logic gates of a computer. It introduces a new component, called a memory cell, which serves as long-term memory and is used in addition to the hidden state memory of classical RNNs. In an LSTM, multiple gates are tasked with reading, adding, and forgetting information from these memory cells. This memory cell acts as a gradient highway, allowing the gateways to pass relatively unhindered through the network. This is the key innovation that avoided vanishing gradients in RNNs.

Let the input to the LSTM at time be , and the hidden state from the previous timestep be . Now, there are three gates that process information. Each gate is nothing but two learnable weight matrices (one for the input and one for the hidden state...