Nouriel Roubini

I believe investors should invest for the long run, so I don't buy and sell. I usually maintain the classic index of global equities, diversified U.S. and global and emerging markets, and when the risk is larger, I diminish the amount in global equities and put more into liquid assets - but very irregularly.

The U.S. has been living in a situation of excesses for too long. Consumers were out spending more than their income and the country was spending more than its income, running up large current-account deficits. Now we have to tighten our belts and save more.

Every time you log in to Facebook, every time you click on your News Feed, every time you Like a photo, every time you send anything via Messenger, you add another data point to the galaxy they already have regarding you and your behavior.