In Chapters, we introduce regression analysis, which addresses the relationships among variables. One of the first applications of regression analysis was to analyze the relationship between the heights of fathers and sons. Suppose that a sample of 80 fathers and sons was drawn. The heights of the fathers and of the adult sons were measured.

a. Draw a scatter diagram of the data. Draw a straight line that describes the relationship.

b. What is the direction of the line?

c. Does it appear that there is a linear relationship between the two variables?