"To make dynamic economic models complete, various expectational formulas have been used. There is, however, little evidence to suggest that the presumed relations bear a resemblance to the way the economy works." - John Muth

Very good. So his infinite moving average of present and past disturbance terms with the coefficients being pi-i-s is also rubbish.

p = p bar + П0w + П1w-1 + П2w-2 + П3w-3 + П4w-4 + ...

MFTTW: "they are trying to forecast a stochastic process?
hahahaha"

"Isn't it interesting that the same people who laugh at science fiction listen to weather forecasts and economists?" - Kelvin Throop III