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What is the purpose of a q-th-order moving average process?
A
To add a fifth error term to an MA(1) process.
B
To add a third error term to an MA(1) process.
C
To add as many additional lagged variables as needed so as to produce a robust set of estimates for the time series.
D
To invert the moving average representation and make it more useful.
Explanation:
A q-th-order moving average process, denoted as MA(q), is used to model time series data where the current value depends on the current error term and q previous error terms.
Key points:
Why other options are incorrect:
Mathematical form of MA(q) process: [ Y_t = \mu + \varepsilon_t + \theta_1\varepsilon_{t-1} + \theta_2\varepsilon_{t-2} + \cdots + \theta_q\varepsilon_{t-q} ] where q represents the order of the moving average process.