“It’s hard to predict, especially the future.”

This quote is often attributed to Albert Einstein, often also to Niels Bohr. Regardless of who said it, we believe it’s true. However, it’s also good news. It tells us two things: first, prediction is hard, not impossible; and second, we predict many things in our lives, not only what is popularly identified as “the future.” Here is an example: When somebody throws a ball at you, you move your hand toward catching it and you often succeed. Martial artists train their brains to identify opponents’ subtle body cues to dodge a punch. Without predicting the punch, dodging would be impossible. And it is not only hard. This anticipation capability of the brain based on sensory input is one of the unsolved topics in multimedia computing.

Of course, at the end of our book we want to give a broader overview than just a very short time prediction over the next couple of milliseconds. For that to not just be a wild guess, we want to introduce a framework that has been proposed in the literature that tries to infer from the past based on the assumption that history repeats in cycles and that the cycle frequency is determined by reputation gains and losses regarding technology.