Exercise 1 Page 700

We are asked to give a definition of bivariate data. Then we should write an example of a data set made up of bivariate data. Let's do it!

Definition

Bivariate data is a set of data that has been collected in two variables. It consists of pairs of numerical observations. Each data value in one variable corresponds to a data value in the other variable.

Example

So far, we analyzed many examples of bivariate data in daily life. A data set with the shoe sizes and heights of people is an example of bivariate data.

Shoe Size	$8$	$7$	$6$	$5$	$7$	$8$	$6$	$7$	$5$
Height (in.)	$63$	$59$	$60$	$55$	$58$	$60$	$56$	$64$	$54$

We suspect that there is an association between the variables. We will see it better in a scatter plot of the data.

See that one variable increases, so does the other. This is why there is a positive association between the variables. Note that the given data is just one example answer. A data set where there is no association between the variables would be equally as good. This means we could exchange the height of the respondents with the number of languages they speak and that would still be an example of bivariate data.