Network analysis literature is filled with many examples of how networks grow over time. Multiple models have been developed to explain the growth of networks, as these patterns differ substantially depending on the sort of network we are analyzing. Network growth has been the subject of a great deal of research and analysis and will not be covered to the same degree in this book. In its place, I will provide an overview of some of the primary growth theories, and set the table for further exploration using Gephi later in this chapter.

What we attempt to understand through observing and predicting network growth is how networks form, how they are likely to grow, and what sort of patterns they exhibit as they are growing. Multiple models exist that attempt to predict network growth using different algorithms, ranging from extremely simple (random graph models) through much more sophisticated approaches that use concepts such as preferential attachment and popularity scores.

Many studies have been done proving that a few systems actually grow in a completely random fashion. So although the random graph models make a useful construct, they do not often mirror real-world networks, except perhaps in some of the contagion scenarios. In these cases, random public contact might occur without intent on the part of either party. We should not dismiss random models too quickly, as they can be used for certain situations; but we should also be aware that their application is limited, and that other approaches are able to simulate or predict the growth of networks far more effectively.

One way to begin exploring network growth is through the use of Gephi generators. These are simple tools that allow you to create different scenarios that can ultimately help you in understanding your own network data, and they can be used as building blocks for in-depth analysis of network patterns. The generators are available as a plugin (Complex Generators) from the Gephi marketplace and can be installed using the same process as other Gephi plugins. To install this or any other plugin, simply navigate to the Tools | Plugins menu and follow the process. Additional information can be found in the Gephi wiki and forums.

Now let's take a look at how these generators can be used to gain an improved understanding of network behavior.