“Fischer Black thought that #markets got the right price within a factor of two about 90 per cent of the time… I knew Fischer pretty well, and he didn’t throw numbers like those around lightly; he thought long and hard about them, even though they sound like the kind of rough figures other people would come up with quickly. We argued quite a bit about them, and I pushed for ‘within a factor of two about half the time’.” —Aaron Brown

*Financial Risk Management for Dummies* chapter 4 = 🔥