IV. Describing Bivariate Data
Prerequisites
none
 Introduction to Bivariate
Data
 Values of the Pearson
Correlation
 Guessing Correlations
Simulation
 Properties of Pearson's
r
 Computing Pearson's
r
 Restriction of
Range Demo
 Variance Sum
Law II
 Exercises
A dataset with two variables contains what is
called bivariate data. This chapter discusses ways to describe
the relationship between two variables. For example, you may
wish to describe the relationship between the heights and weights
of people to determine the extent to which taller people weigh
more.
The introductory section gives more examples
of bivariate relationships and presents the most common way of
portraying these relationships graphically. The next five sections
discuss Pearson's correlation, the most common index of the relationship
between two variables. The final section, "Variance
Sum Law II"
makes use of Pearson's correlation to generalize this law to
bivariate data.
