Consider the Monthly Time Series Shown in the Table A Use the Method of Least Squares to Fit the {\text

question 27

Essay

Consider the monthly time series shown in the table. $\begin{array}{l|c|c}\hline {\text { Month }} & \mathrm{t} & \mathrm{Y} \\\hline \text { January } & 1 & 185 \\\hline \text { February } & 2 & 192 \\\hline \text { March } & 3 & 189 \\\hline \text { April } & 4 & 201 \\\hline \text { May } & 5 & 195 \\\hline \text { June } & 6 & 199 \\\hline \text { July } & 7 & 206 \\\hline \text { August } & 8 & 203 \\\hline \text { September } & 9 & 208 \\\hline \text { October } & 10 & 209 \\\hline \text { November } & 11 & 218 \\\hline \text { December } & 12 & 216 \\\hline\end{array}$

a. Use the method of least squares to fit the model $\mathrm { E } \left( \mathrm { Y } _ { \mathrm { t } } \right) = \beta _ { 0 } + \beta _ { 1 } \mathrm { t }$ to the data. Write the prediction equation.
b. Construct a residual plot for the model.
c. Is there evidence of a cyclical component? Explain.

Identify the appropriate types of visuals for various data presentation needs.

Understand and explain the role and power of visual elements in business communication.

Recognize ethical considerations in the use of visuals.

Understand how visuals can enhance message completeness and persuasiveness.

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Definitions:

Absorption Costing

A cost accounting method that includes all manufacturing costs - direct materials, direct labor, and both variable and fixed overheads - in the cost of a unit of product.

Gross Margin

The difference between the revenue generated from sales and the cost of goods sold, representing the profit made before accounting for operating expenses.

Operations

Operations refer to the day-to-day activities involved in the running of a business for the purpose of producing value for the stakeholders.

Variable Costing

An accounting method that includes only variable production costs in the cost of goods sold, excluding fixed factory overhead.