The majority of finance makes the assumption that investors are familiar with statistics like means, standard deviations, and betas, as if you were aware of the mechanism responsible for creating the unpredictability. It's a leap of faith to do this. In the real world, previous data can aid in future prediction, but it is not perfect. Historical means (returns) do not accurately predict their future equivalent means; however, historical risks and correlations tend to be good predictor of future risks and correlations. True False