A Forecaster Used the Regression Equation $Q _ { t } = a + b t + c _ { 1 } D _ { 1 } + c _ { 2 } D _ { 2 } + c _ { 3 } D _ { 3 }$

question 28

Multiple Choice

A forecaster used the regression equation $Q _ { t } = a + b t + c _ { 1 } D _ { 1 } + c _ { 2 } D _ { 2 } + c _ { 3 } D _ { 3 }$ and quarterly sales data for 2004I-2021IV (t = 1,...,64) for an appliance manufacturer to obtain the results shown below.Q is quarterly sales,and $D _ { 1 } , D _ { 2 }$ and $D _ { 3 }$ are dummy variables for quarters I,II,and III. What is the estimated intercept of the trend line in the fourth quarter?

• A)0
• B)40
• C)55
• D)70
• E)none of the above

---

Definitions:

Coefficient of Determination

A statistical measure represented by R^2, which shows the proportion of variance in the dependent variable that is predictable from the independent variables.

Sum of Squares

A statistical measure that quantifies the variance or dispersion of a set of numbers by summing the squared differences between each number and the mean.

Error SSE

The sum of squared errors (SSE) is a measure used in statistics to quantify the discrepancy between the data and an estimation model.

Coefficient of Determination

A statistical measure that expresses the proportion of variance in the dependent variable that can be predicted from the independent variable(s).