Just a quick excerpt from Quantifiable Edges,
"What needs to be kept in mind is that the price action over the last week has been more severe than at any time other than 1987 and then back to the 1930’s. In other words, while extreme readings in breadth, volatility, price, and volume indicators of this magnitude have almost always led to short-term upside over the periods tested, the current situation is far beyond most everything tested. Measures need to be taken to control risk. Tight stops are a possibility, but difficult to implement with such extreme volatility. I’m controlling risk by scaling in with reduced position size."
