I wonder that when we calculate the AIC, what is the number of free parameters i
ID: 3173189 • Letter: I
Question
I wonder that when we calculate the AIC, what is the number of free parameters in each model, AR(2), MA(1), and ARMA(2,1)?? 3. The three models AR(2), MA(1), and ARMA(2.1) are fitted to the following time series: Year Quarter 1 IQuarter 2 Quarter 3 Quarter 4 101 2011 105 106 110 2012 106 The results using R are as follows: AR(2 MA(1): arl mal intercept 0.2618 00868 0.1899 103.798 0.3326 1.7373 st. error 0.3289 2.372 st. error 0.2574 og likelihood -36 arl ar2 mal intercept -0.6317 0,4137 0.9 101.4512 ARMA (2,1) st. error 0,3329 0.38267 0.235 2.4584 log likelihood E3602 21.31 The models are ranked using Akaike Information Criterion (AIC): AIC -2x log likelihood +2 x number of free parameters. Determine the order from the best to worst model. Give full explanation on how you arrived to your answer, Show calculations. A. AR (2), MA(1), ARMA (2,1) B. AR(2), ARMA (2,1), MA(1) C. MA(1), AR(2), ARMA (2,1) D. MA(1), ARMA (2,1), AR (2) E. ARMA (2.1), AR(2), MA (1).Explanation / Answer
i think in MA(1) process standard error is very less compaire to other process. then AR(2) process standard error is less than ARMA (2,1) process. hence in which process error is less this is best model.
option C is right answer