Regression Analysis Introduction
•Recall in chapter 4 we used Applewood Auto Group data to show the relationship between two variables using a scatter diagram. The profit for each vehicle sold and the age of the buyer were plotted on an XY graph
•The graph showed that as the age of the buyer increased, the profit for each vehicle also increased
•This idea is explored further here. Numerical measures to express the strength of relationship between two variables are developed.
•In addition, an equation is used to express the relationship between variables, allowing us to estimate one variable on the basis of another.
EXAMPLES
Does the amount Healthtex spends per month on training its sales force affect its monthly sales?
in Is the number of square feet in a home related to the cost to heat the home January?
per gallon and the In a study of fuel efficiency, is there a relationship between miles weight of a car?
the exam Does the number of hours that students studied for an exam influence 13-3 score?