Q5. The mean reverting level for the first equation is closest to: A) -0.8. B) 20.0. C) 43.6.
Q6. Based upon the output provided by Collier to his supervisor and without any further calculations, in a comparison of the two equations’ explanatory power of warranty expense it can be concluded that: A) the autoregressive model on the first differenced data has more explanatory power for warranty expense. B) the provided results are not sufficient to reach a conclusion. C) the two equations are equally useful in explaining warranty expense.
Q7. Based on the autoregressive model, expected warranty expense in the first quarter of 2005 will be closest to: A) $78 million. B) $65 million. C) $60 million.
Q8. Based upon the results, is there a seasonality component in the data? A) No, because the slope coefficients in the autoregressive model have opposite signs. B) Yes, because the coefficient on yt is small compared to its standard error. C) Yes, because the coefficient on yt-4 is large compared to its standard error.
Q9. Collier most likely chose to use first-differenced data in the autoregressive model: A) to increase the explanatory power. B) in order to avoid problems associated with unit roots. C) because the time trend was significant.
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发表于 2009-1-10 17:26
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