Small World Simulation - The Alpha Model

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WHAT IS IT?

This model shows the behaviour of the "small world" phenomenon according to Duncan Watts "alpha" model. It demonstrates the transition from a "cave-man-world" (which is a highly clustered world with no connection between the "caves") to a "solaris" world (a completely random graph).


HOW IT WORKS

With every increment of the alpha parameter (one step), a connection in a cave is deleted and rewired to a random other cave.


HOW TO USE IT

To start the modelling you have to setup the initial graph by pressing "setup". If you want to increase the alpha parameter till the graph is completely random, you can launch the model by pressing "run" or step by step via pressing "step" (here you can also adjust the step size). The plot illustrades the current average-path-length and the clustering-coefficient.


THINGS TO NOTICE

Explore the behaviour of the average-path-length (L) and the clustering-coefficient (C) during a run.


THINGS TO TRY

Vary the number of nodes (persons) and the number of persons in a cave and redo the modelling process


CREDITS AND REFERENCES

This small world model is adopted from: Duncan J. Watts, Six Degrees: The Science of a Connected Age, W.W. Norton & Company, New York 2003, pages 76-82

Implemented by Georg Reinisch.

Markus Strohmaier