Читать книгу Asset Allocation - William Kinlaw, Mark P. Kritzman - Страница 15

 It is widely assumed that investing over long horizons is less risky than investing over short horizons, because the likelihood of loss is lower over long horizons.

 Paul A. Samuelson showed that time does not diversify risk because, though the probability of loss decreases with time, the magnitude of potential losses increases with time.

 It is also true that the probability of loss within an investment horizon never decreases with time.

 Finally, the cost of a protective put option increases with time to expira-tion. Therefore, because it costs more to insure against losses over longer periods than shorter periods, it follows that risk does not diminish with time.