Scatterplot & Method of Least Squares Linear Regression Assignment QikLube is a car care center specializing...

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Scatterplot & Method of Least Squares Linear Regression Assignment QikLube is a car care center specializing in fast oil changes. QikLube has two service spaces, which limits its capacity to 3,600 oil changes per month. The company accountant believes operating expenses are driven by the number of oil changes. The following information was collected over the past six months: Month Number of Oil Changes Operating Expenses January 3,200 $129,570 February 2,800 $123,000 March 2,600 $111,800 April 2,700 $115,400 May 3,600 $135,075 June 2,900 $120,500 Required Part I (handwritten): 1. Prepare a scatterplot graphing the volume of oil changes against the company's monthly operating expenses. Graph by hand and draw the line you believe best fits the data. 2. Based on the scatterplot, how strong of a relationship does there appear to be between the company's operating expenses and the number of oil changes performed each month? Explain what factors you considered in making this judgment. Part II (in Excel): 3. Using Microsoft Excel, run a linear regression and submit the Summary Output. Include the following on the Summary Output or on a separate page (for example, separate Excel worksheet or Word document): a. Identify and interpret the coefficient of determination (adjusted). b. Identify and interpret the coefficient of correlation. c. Indicate the general cost formula (equation), round fixed cost to the nearest whole dollar and the variable cost to two decimal places (if rounding necessary). 4. Estimate operating expenses when 4,000 oil changes are expected. Would you feel comfortable using this estimate to project operating costs? Explain why or why not? Scatterplot & Method of Least Squares Linear Regression Assignment QikLube is a car care center specializing in fast oil changes. QikLube has two service spaces, which limits its capacity to 3,600 oil changes per month. The company accountant believes operating expenses are driven by the number of oil changes. The following information was collected over the past six months: Month Number of Oil Changes Operating Expenses January 3,200 $129,570 February 2,800 $123,000 March 2,600 $111,800 April 2,700 $115,400 May 3,600 $135,075 June 2,900 $120,500 Required Part I (handwritten): 1. Prepare a scatterplot graphing the volume of oil changes against the company's monthly operating expenses. Graph by hand and draw the line you believe best fits the data. 2. Based on the scatterplot, how strong of a relationship does there appear to be between the company's operating expenses and the number of oil changes performed each month? Explain what factors you considered in making this judgment. Part II (in Excel): 3. Using Microsoft Excel, run a linear regression and submit the Summary Output. Include the following on the Summary Output or on a separate page (for example, separate Excel worksheet or Word document): a. Identify and interpret the coefficient of determination (adjusted). b. Identify and interpret the coefficient of correlation. c. Indicate the general cost formula (equation), round fixed cost to the nearest whole dollar and the variable cost to two decimal places (if rounding necessary). 4. Estimate operating expenses when 4,000 oil changes are expected. Would you feel comfortable using this estimate to project operating costs? Explain why or why not?