MAProcess
MAProcess[{b1,…,bq},v] represents a moving-average process of order q with normal white noise variance v.
MAProcess[{b1,…,bq},Σ] represents a vector MA process with multinormal white noise covariance matrix Σ.
MAProcess[{b1,…,bq},v,init] represents an MA process with initial data init.
MAProcess[c,…] represents an MA process with a constant c.
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