The Acf Is Clearly Declining Very Slowly in This Case

question 18

Multiple Choice

The acf is clearly declining very slowly in this case, which is consistent with their being an autoregressive part to the appropriate model. The pacf is clearly significant for lags one and two, but the question is does it them become insignificant for lags 2 and 4, indicating an AR(2) process, or does it remain significant, which would be more consistent with a mixed ARMA process? Well, given the huge size of the sample that gave rise to this acf and pacf, even a pacf value of 0.001 would still be statistically significant. Thus an ARMA process is the most likely candidate, although note that it would not be possible to tell from the acf and pacf which model from the ARMA family was more appropriate. The DGP for the data that generated this plot was y_t = 0.9 y_(t-1) - 0.3 u_(t-1) + u_t.
-What is the optimal three-step ahead forecast from the AR(2) model given in question 14?

• A) -0.1
• B) 0.27
• C) -0.34
• D) -0.31

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Definitions:

Discretionary Task

refers to a job or an assignment that requires personal judgment or choice in its execution, often without strict guidelines or procedures.

Process Loss

Reduction in group performance compared to individual performance, often due to coordination and motivation problems.

Steiner's Taxonomy

is a classification system for group tasks developed by Ivan Steiner, categorizing them based on their nature, such as additive, disjunctive, conjunctive, and compensatory.

Group's Product

The outcome, idea, or solution generated through collaborative efforts within a group.