I just read this article. It basically argues that you can tell which way the market is headed by thinking of total available cash to invest as demand and total available equity as supply, and then looking at the relationship between the two.
So, when there's an imbalance too far in one way, the market will tend to correct in the other way. It's a new idea; I'm wondering if anybody here has played with this concept before?
I'm also curious to hear if anybody has an idea of how to get this data into Quantopian to play with.