ON PC SOLUTIONS OF PARMA
MODELS
Abstract: This note is concerned with the existence of periodically correlated solutions for the
PARMA
system
where

is a white noise and the varying coefficients

and

are periodic in

with
period

Conditions which ensure the existence of periodically correlated solutions for
such systems are obtained.
2000 AMS Mathematics Subject Classification: 62M10, 60G10.
Key words and phrases: ARMA models, PARMA models, periodically correlated.