Census Zip Code data versus internal data as predictors of alumni giving

Guest post by Peter Wylie and John Sammis

Thanks to data available via the 2010 US Census, for any educational institution that provides us zip codes for the alums in its advancement database, we can compute such things as the median income and the median house value of the zip code in which the alum lives.

Now, we tend to focus on internal data rather than external data. For a very long time the two of us have been harping on something that may be getting a bit tiresome: the overemphasis on finding outside wealth data in major giving, and the underemphasis on looking at internal data. Our problem has been that we’ve never had a solid way to systematically compare these two sources of data as they relate to the prediction of giving in higher education.

John Sammis has done a yeoman’s job of finding a very reasonably priced source for this Census data as well as building some add-ons to our statistical software package – add-ons that allow us to manipulate the data in interesting ways. All this has happened within the last six months or so, and I’ve been having a ball playing around with this data, getting John’s opinions on what I’ve done, and then playing with the data some more.

The data for this piece come from four private, small to medium sized higher education institutions in the eastern half of the United States. We’ll show you a smidgeon of some of the things we’ve uncovered. We hope you’ll find it interesting, and we hope you’ll decide to do some playing of your own.

Download the full, printer-friendly PDF of our study here (free, no registration required): Census ZIP data Wylie & Sammis.