Skip to main content

NY City Public Schools, and what they might tell us about the SAT

Recently, I received a message from Akil Bello who pointed out a data visualization he had seen.  It was originally posted to Reddit, but later was edited to eliminate the red-green barrier that people with color-blindness face.  The story was here, using a more suitable blue-red scheme.

There's nothing really wrong with visualizing test scores, of course.  I do it all the time.  But many of the comments on Reddit suggest that somehow the tests have real meaning, as a single variable devoid of any context.  I don't think that's a good way to analyze data.

So I went to the NY City Department of Education to see what I can find.  There is a lot of good stuff there, so I pulled some of it down and began taking a look at it.  Here's what I found.

On the first chart, I wanted to see if the SAT could be described as an outcome of other variables, so I put the average SAT score on the y-axis, and began with a simple measure: Eighth grade math and English scores on the x-axis. Hover over the regression line, and you'll see an r-squared of about .90.

Scientists would use the term "winner, winner, chicken dinner" when getting results like this.  It means, for all intents and purposes, that if you know a high school's mean 8th grade achievement scores, you can predict their SAT scores four years later with amazing accuracy.  And--here's the interesting thing--the equation holds for virtually every single school.  There are few outliers.

Ponder that.

But critics of the SAT also say that the scores are reflective of other things, too; an accumulation of social capital, for instance.  So use the control at the bottom to change the value on the x-axis.  Try economic need index, or percentage of students in temporary housing, or percentage of the student body that are White or Asian. The line may go up (positive correlation) or down (negative) but you'll always see the schools with the highest scores tend to have the characteristics you'd expect.

Jump to the second tab.  This is more a response to the Reddit post: The top map shows the ZIP codes and a bubble, indicating the number of schools in that ZIP.  The bottom map shows every school arrayed on two poverty scales: Economic Index and Percent in Temporary Housing.  The color shows the mean SAT score in the school (Critical Reading plus Math, on a 1600-point scale.)  Purple dots represent higher scores.

Use the ZIP highlighter, and you'll see the top map show only that bubble, and the bottom will show the schools in it.

Got the lesson?  Good.  Now, think about why the colleges with high median test scores a) have them, and b) tend to produce students with high GRE and MCAT and LSAT scores,  and c) point to excellent outcomes for their students.

And let me know what you think.






Comments

Popular posts from this blog

The Highly Rejective Colleges

If you're not following Akil Bello on Twitter, you should be.  His timeline is filled with great insights about standardized testing, and he takes great effort to point out racism (both subtle and not-so-subtle) in higher education, all while throwing in references to the Knicks and his daughter Enid, making the experience interesting, compelling, and sometimes, fun. Recently, he created the term " highly rejective colleges " as a more apt description for what are otherwise called "highly selective colleges."  As I've said before, a college that admits 15% of applicants really has a rejections office, not an admissions office.  The term appears to have taken off on Twitter, and I hope it will stick. So I took a look at the highly rejectives (really, that's all I'm going to call them from now on) and found some interesting patterns in the data. Take a look:  The 1,132 four-year, private colleges and universities with admissions data in IPEDS are incl

The College Finder

Note: A few people have commented on slow loading with the visualization.  If you have troubles, click here to be taken right to the visualization .  It should open in a new tab and you can follow along from there.    This is always a popular post with high school counselors, IECs, parents, and students who are looking for general information on degrees awarded, or a very specific combination of academic programs, location, and other institutional characteristics. It uses IPEDS data I downloaded as soon as I can when it became available (and before a looming government shutdown), and shows all 1,700 majors recognized by the federal government in the IPEDS system, using CIP codes, and the number of degrees awarded by college in any selected area. For instance, you might have a question about which college awards the most degrees in French Language and Literature: A few clicks, and you find it's the University of Arizona.  If you want a colder climate, choose the Great Lakes region,

Freshman Migration, 1986 to 2020

(Note: I discovered that in IPEDS, Penn State Main Campus now reports with "The Pennsylvania State University" as one system.  So when you'd look at things over time, Penn State would have data until 2018, and then The Penn....etc would show up in 2020.  I found out Penn State main campus still reports its own data on the website, so I went there, and edited the IPEDS data by hand.  So if you noticed that error, it should be corrected now, but I'm not sure what I'll do in years going forward.) Freshman migration to and from the states is always a favorite visualization of mine, both because I find it a compelling and interesting topic, and because I had a few breakthroughs with calculated variables the first time I tried to do it. If you're a loyal reader, you know what this shows: The number of freshman and their movement between the states.  And if you're a loyal viewer and you use this for your work in your business, please consider supporting the costs