In chapter 5 we learned how to analyze and describe univariate, or single-variable data. We explored ways to present our data visually with graphs and charts and how to analyze our data with numerical statistics. Also, we described our findings verbally and in context. Now we will be analyzing bivariate numerical data. This means two numerical values collected about each individual. Such bivariate data is often given in a table, or can be listed as ordered pairs. We will construct appropriate graphs, calculate numerical statistics and equations, and describe the relationship between the two variables in context. The purpose will be to explore whether or not a relationship or association exists between the two numerical variables. If an association does exist, statistics can be used to predict one variable based on the other variable.