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

Handling non-stationarity in time series

Stationarity is a prevalent assumption in econometrics and is a rigorous and mathematical concept. But without getting into a lot of math, we can intuitively think about stationarity as the state where the statistical properties of the distribution from which the time series is sampled remain constant over time. This is relevant in time series as regression as well because we are estimating a single forecasting function across time. And if the behavior of the time series changes with time, the single function that we estimate may not be relevant all the time. For instance, if we think about the number of visitors to the nearby park in a day as a time series, we know that those patterns are going to be very different for pre- and post-pandemic periods. In the ML world, this phenomenon is called concept drift.

Intuitively, we can understand that it is easier to forecast a stationary series than a non-stationary series. But here comes the punchline...