A scatterplot is a graph that gives you a visual display of two variables in a data set. It lets you "see" the data! For example, this scatterplot lets you "see" the relationship between students' attitudes toward mathematics and their achievement in mathematics.

Each data point in this case represents a person's score on an attitude toward mathematics survey and their score on a mathematics achievement test. For example, two students scored 40 on the attitude survey and their scores on the math test were 54 and 56. The student who scored 80 on the attitude survey had a 65 on the achievement test. Each point on the scatterplot represents a "pair" of scores.

It is often useful to do a scatterplot of the variables in a data set. Looking at the data visually lets you "see" trends, groups of data points, gaps between data points and outliers that descriptive statistics do not reveal.

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