Wednesday, May 6, 2009

Age Distribution at ICC

Apropos a discussion over at Dean Dad's blog, here is an approximate, randomly normalized histogram of the age distribution of students at Ishkabibble Community College at some point in the not too distant past.

Details below the fold.

It actually does look a bit like the Maxwell-Boltzmann distribution, as I mentioned in a comment over at DD's blog, but it could just as well be a Lorentzian, or any of several other shapes with a long tail.

Lacking any better information (these are from some of the data our institution is required to make publicly available so they are easily obtained), I put everyone in the "under 18" category in a bin at 17 years old, and spread the population in large age bins uniformly across those ranges. You probably can't see that there is an actual thin line above age 55.

You can see that the peak (mode) is at 19. The average (mean) is around 24, and the median (half above, half below) is around 20. Most (if not all) of the students in the 17 year old bin are probably dual-enrolled high school students.

As I said in my comment at DD's, we are primarily a transfer institution where a large fraction of our students come to us directly out of high school. If you take the AACS Fast Facts, the subject of DD's blog, at face value, we are far below the national mean age of 29 and also below the likely value of the national median age, 22.

An important detail:
This data set is only for classes taken for credit and excludes a large number of students who are taking various non-credit "workforce" classes that we offer. They make up about 15% of our total student body and probably have a very different age distribution. If those were included, and they could be included in the AACC stats, our average age would likely increase.

No comments: