# Scatter diagram, regression

Scatter diagram, regression

Quick-print firms in a large downtown business area spend most of their advertising dollars on advertisements on bus benches. A research project involves predicting monthly sales based on the annual amount spent on placing ads on bus benches. A sample of quick-print firms revealed these advertising expenses and sales.

Annual Bus Bench Advertising

($ thousands) Monthly Sales

($ thousands)

2 40

4 55

5 75

7 80

3 45

a. Draw a scatter diagram.

b. Determine the coefficient of correlation.

c. What is the coefficient of determination?

d. Compute the regression equation.

e. Estimate the monthly sales of a quick-print firm that spends $4,500 on bus bench advertisements.

f. Summarize your findings.

https://brainmass.com/statistics/regression-analysis/scatter-diagram-regression-estimated-8637

#### Solution Preview

a) Shown in the excel sheet

b)Coefficient of correlation = R^2 = .913 ( from the graph).

So R = .955

c)Coefficient of Determination = 8.8514 ( Frm the graph)

d)Regression Equation : ...

#### Solution Summary

The expert draws a scatter diagram. The coefficient of correlation is determined. Monthly sales of a quick-print firm that spends money on bench advertising is estimated.