How do you read a scatterplot?

When you select a grade, subject, and group from the drop-down menus, the State Academic Performance and Improvement tool will create a scatterplot that shows how each state performed in 2015 and how much it improved between 2003-2015 for that group, subject, and grade. Below is an example scatterplot that shows the results for Latino students in eighth-grade math.


Each dot in the scatterplot represents a state. Improvement is shown across the horizontal axis. The further to the right a state appears, the faster it is improving; the further to the left – the more slowly.

Performance appears on the vertical axis. States higher up in the chart are higher performing; those toward the bottom are lower performing.
The two green axes intersect at the national average; in the chart above, for example, we see that the nation as a whole improved Latino eighth-graders’ performance in math by about 11 points since 2003. We also see that in 2015, the national average scale score for this group was 269. To learn more about NAEP and NAEP scale scores, click here.

What does a scatterplot tell you?

Comparisons to national averages

Scatterplots offer another way of gauging how a state’s performance and gains compare to the national average. States that appear in the upper right-hand quadrant were higher improving and higher performing than the nation as a while, while states in the lower left-hand quadrant showed lower improvement and lower performance than national averages. States in the upper left-hand quadrant showed higher performance, but lower improvement than the nation. And those in the bottom right-hand quadrant were lower performing, but showed higher improvement than the nation.

Comparisons among states

In addition to showing how states compare with national averages, the scatterplots also demonstrate how states compare with each other. As the scatterplot above shows, Latino students’ achievement in eight-grade math looks very different in New Jersey than it does in New York. Latino eighth-graders are performing better and improving faster in math in New Jersey than Latino eighth-graders in New York.