The formula for the sample autocorrelation Select one: a. is equal ?1 in an AR(1) model. b. does not depend on the sample size T. c. allows for the variance of the time series to be a function of time. d. implicitly assumes that the time series is stationary.
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Step 1: The formula for the sample autocorrelation is given by \( C_k = \frac{Y_k}{Y_0} \), where \( Y_k \) is the autocovariance \( \gamma(k) \) and \( Y_0 \) is the variance of the time series. Show more…
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