Ploting the Data

Yesterday I looked at SAT scores in Maryland by county and income and for the incoming freshman classes of the public four-year institutions. Today I take a brief look at SAT scores by county and race/ethnicity from the same dataset published by the Maryland State Department of Education. I made a dot plot using Datawrapper with all the race/ethnicity categories available in the data set as well as “all students”. To be honest, the chart looks very busy and is rather hard to read. I changed the color scheme to reds and oranges to aid with distinguishing the categories, but it only helped a little. I could choose custom colors for each group, and would if I was intending to show this data to a wider audience, but since this is primarily for my own exploration of the data I decided I did not have the energy to make those choices today. I did decide to highlight the “all student” category to help with readability a bit.

An alternative visualization, and the one I have seen used at State Board of Education meetings, is a grouped bar chart. While I think that would work for smaller numbers of counties or race/ethnicities, I think that it is worst than the dot plot for a large amount of data. However, I may explore this visualization in the future.

SAT SCores by county and Race/Ethnicity

It is hard to draw any conclusions from this data. For one thing, I am unsure if this data represents public school students or all students who took the test from that county. For another thing, not all students take the SAT and different local school systems have different policies about pushing students to take the SAT.

Howard County stands out as having very high scores, for students of all races. From the data, I do not know if Howard County encouraged only high-performing students to take the SAT. I would be surprised if that was the case, but it is a possibility. Since there is information about the number of students that took the test, I might be able to infer the policy from that data or I might look at their website to see if they have a SAT policy.

Note: I likely will not be posting for a while as I will be on vacation.