"Although the Efficient Markets Hypothesis has been the dominant theory of financial markets for decades, it’s clear that individuals aren’t always rational. We shouldn’t be surprised, then, that markets aren’t always efficient, because Homo sapiens isn’t Homo economicus. 

"We’re neither entirely rational nor entirely irrational, hence neither the rationalists nor the behavioralists are completely convincing. We need a new narrative for how markets work, and now have enough pieces of the puzzle to start putting it all together.

"We begin with this simple acknowledgment: market inefficiencies do exist.  When examined together, these inefficiencies and the behavioral biases that create them are important clues into how that complicated neurological system, the human brain, makes financial decisions."