Let $\epsilon_t \sim i.i.d.N(-2, 9)$. In addition, $y_t$ follows the process in (1): $y_t = 1 + 0.75y_{t-1} + 0.25y_{t-2} + \epsilon_t$ 1. What does it mean for a process to be stationary? Answer: 2. Is $y_t$ in eqn (1) stationary? Explain. Answer: (1)
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