The 80/20 Rule Devoted himself to finding laws in economics, trying to make it into an exact science. Author of the three-volume Trattato di Sociologia Generale First noticed the 80/20 Rule Pareto’s Law of Principle Vilfredo Pareto

Examples of the 80/20 Rule 80% of Pareto’s peas came from 20% of the peapods. 80% of Italy’s land was owned by 20% of the people 80% of profit is produced by 20% of employees. 80% of crime is committed by 20% of the criminals.

Bell Curve In this example, we see the IQ score and the % of the population. A Bell Curve does not allow IQ under 0 or over 165 in this modell. General rule is that most will be at the center of the curve, while a few will be on the left and right side.

Power Law In a Bell Curve you don’t allow the very very “unusual” event. The web and number of links follow a power law.

The web and the distribution of links follow a power law, and that shows us that there are a few hubs that has millions of links, but the average is a much smaller number. (1999) Erdòs and Rènyi, along with Watts and Strogatz, both told us that nodes with k links should decrease exponentially. They both told us that hubs do not exist. If the 80/20 Rule applies, the distribution can be shown as a power law.

Phase Transition Water to ice. Metal to magnet. From disorder to order. After the transition they follow power laws. (?) How does order emerge from disorder?

The answer Kenneth Wilson ( ) Renormalization Nobel prize in physics 1982