Book Image

Hands-On Graph Neural Networks Using Python

By : Maxime Labonne
Book Image

Hands-On Graph Neural Networks Using Python

By: Maxime Labonne

Overview of this book

Graph neural networks are a highly effective tool for analyzing data that can be represented as a graph, such as networks, chemical compounds, or transportation networks. The past few years have seen an explosion in the use of graph neural networks, with their application ranging from natural language processing and computer vision to recommendation systems and drug discovery. Hands-On Graph Neural Networks Using Python begins with the fundamentals of graph theory and shows you how to create graph datasets from tabular data. As you advance, you’ll explore major graph neural network architectures and learn essential concepts such as graph convolution, self-attention, link prediction, and heterogeneous graphs. Finally, the book proposes applications to solve real-life problems, enabling you to build a professional portfolio. The code is readily available online and can be easily adapted to other datasets and apps. By the end of this book, you’ll have learned to create graph datasets, implement graph neural networks using Python and PyTorch Geometric, and apply them to solve real-world problems, along with building and training graph neural network models for node and graph classification, link prediction, and much more.
Table of Contents (25 chapters)
1
Part 1: Introduction to Graph Learning
5
Part 2: Fundamentals
10
Part 3: Advanced Techniques
18
Part 4: Applications
22
Chapter 18: Unlocking the Potential of Graph Neural Networks for Real-World Applications

Comparing graph convolutional and graph linear layers

In the previous chapter, our vanilla GNN outperformed the Node2Vec model, but how does it compare to a GCN? In this section, we will compare their performance on the Cora and Facebook Page-Page datasets.

Compared to the vanilla GNN, the main feature of the GCN is that it considers node degrees to weigh its features. Before the real implementation, let’s analyze the node degrees in both datasets. This information is relevant since it is directly linked to the performance of the GCN.

From what we know about this architecture, we expect it to perform better when node degrees vary greatly. If every node has the same number of neighbors, these architectures are equivalent: ():

  1. We import the Planetoid class from PyTorch Geometric. To visualize the node degrees, we also import matplotlib and two additional classes: degree to get the number of neighbors of each node and Counter to count the number of nodes for each...