... Most generally, noise makes it very difficult to test either practical or academic theories about the way that financial or economic markets work. We are forced to act largely in the dark. ...
ใ กFischer Black, Noise, 1986, Journal of Finance
... Our general message is universal: Because of the high volatility of stock returns, investors cannot draw strong inferences about expected returns from 3, 5, or even 10 years of realized returns. Those who act on such noisy evidence should reconsider their approach. ... (๋ ์์๋ณด๊ธฐ)
ใ กFama and French, Volatility Lessons, 2018, FAJ