Which of the Following Is Not a Necessary Condition for a Variable

question 2

Multiple Choice

Which of the following is not a necessary condition for a variable to be stationary?

• A)E(y_t)= \(\mu\)
• B)var(y_t)= \(\sigma\) ²
• C)cov(y_t,y_t+s)= cov(y_t,y_t-s)= \(\gamma\)_s
• D)E(y_t - y_t-1)= \(\pi\)

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