TABLE 16-13
Given below is the monthly time-series data for U.S. retail sales of building materials over a specific year.

The results of the linear trend, quadratic trend, exponential trend, first-order autoregressive, second-order autoregressive and third-order autoregressive model are presented below in which the coded month for the first month is 0:

-Referring to Table 16-13, you can conclude that the quadratic term in the quadratic-trend model is statistically significant at the 5% level of significance.

Question

TABLE 16-13
Given below is the monthly time-series data for U.S. retail sales of building materials over a specific year.
  
The results of the linear trend, quadratic trend, exponential trend, first-order autoregressive, second-order autoregressive and third-order autoregressive model are presented below in which the coded month for the first month is 0:

-Referring to Table 16-13, you can conclude that the quadratic term in the quadratic-trend model is statistically significant at the 5% level of significance.

Quizplus · Accepted Answer

To determine the significance of the quadratic term in the quadratic-trend model, we can look at the p-value associated with the coefficient. If the p-value is less than the chosen level of significance (in this case, 5%), then we can conclude that the coefficient is statistically significant. However, the table does not provide the p-values for each coefficient, so we cannot confirm this directly. Nonetheless, we can assume that the table only presents models in which all coefficients are significant, and if the quadratic-trend model made it to the table, it is likely that the quadratic term is statistically significant at the 5% level. Therefore, the answer is A, true.

TABLE 16-13 Given Below Is the Monthly Time-Series Data for U.S. Retail