Book Image

Codeless Time Series Analysis with KNIME

By : KNIME AG, Corey Weisinger, Maarit Widmann, Daniele Tonini
Book Image

Codeless Time Series Analysis with KNIME

By: KNIME AG, Corey Weisinger, Maarit Widmann, Daniele Tonini

Overview of this book

This book will take you on a practical journey, teaching you how to implement solutions for many use cases involving time series analysis techniques. This learning journey is organized in a crescendo of difficulty, starting from the easiest yet effective techniques applied to weather forecasting, then introducing ARIMA and its variations, moving on to machine learning for audio signal classification, training deep learning architectures to predict glucose levels and electrical energy demand, and ending with an approach to anomaly detection in IoT. There’s no time series analysis book without a solution for stock price predictions and you’ll find this use case at the end of the book, together with a few more demand prediction use cases that rely on the integration of KNIME Analytics Platform and other external tools. By the end of this time series book, you’ll have learned about popular time series analysis techniques and algorithms, KNIME Analytics Platform, its time series extension, and how to apply both to common use cases.
Table of Contents (20 chapters)
1
Part 1: Time Series Basics and KNIME Analytics Platform
7
Part 2: Building and Deploying a Forecasting Model
14
Part 3: Forecasting on Mixed Platforms

Autocorrelation

One of the most distinctive characteristics of a time series is the mutual dependence between the observations. In fact, it’s important in Time Series Analysis to focus on the relationship between the lagged values of a time series.

In bivariate statistics, to analyze the relationship between two numerical variables, the Pearson linear correlation index is probably the most used (and abused) association metric. The correlation index is a relative (symmetric) measure of the linear relationship existing between two quantitative variables, X and Y, and it’s calculated as follows:

Where:

  • is the sample covariance between X and Y.
  • and are the sample standard deviation of X and Y.

Just as the correlation index measures the linear relationship between two variables X, the autocorrelation index measures the linear relationship between the lagged values of a time series. As the standard deviation and the mean...