In 2007, I analyzed data on student charitable giving at University of Zurich, broken down by major. When paying registration fees, students at Zurich could choose to give to one or both of two charities (one for foreign students, one for needy students). Among large majors, philosophy students proved the most charitable of all majors. However, philosophy majors' rates of charitable giving didn't rise over the course of their education, suggesting that their giving rates were not influenced by their undergraduate training.
I now have some similar data from University of Washington, thanks to Yoram Bauman and Elaina Rose. At UW from 1999-2002, when students registered for courses, they had the opportunity to donate to two charities: WashPIRG (a broadly left-leaning activist group) and (starting in fall 2000) "Affordable Tuition Now" (an advocacy group for reducing the costs of higher education in Washington). Bauman and Rose published an analysis of economics students' charity and they kindly shared their raw data with me for reanalysis. My analysis focuses on undergraduates under age 30.
First, looking major-by-major (based on final declared primary major at the end of the study period), we see that philosophy students are near the top. The main dependent measure is, in any given term, what percentage of students in the major gave to at least one of the two charities. Among majors with at least 1000 student enrollment terms, the five most charitable majors were:
Major: percent giving
Comparative History of Ideas: 31%
International Studies: 24%
The five least charitable were:
Construction Management: 7%
Business Administration: 7%
These numbers compare with a 14% donation rate overall.
As reported by Bauman and Rose and also in Frey and Meier 2003 (the original source of my Zurich data), business and economics majors are among the least charitable. The surprise here (to me) is sociology. In the Zurich data, sociology majors are among the most charitable. (Hypotheses welcome.)
But what is the time course of donation? Bauman and Rose and Frey and Meier found that business and economics students were among the least charitable from the very beginning of their education and their charity rates did not decline further. Thus, they suggest, their low rates of charity are a selection effect -- an effect of who tends to choose such majors -- rather than a result of college-level economics instruction. My analysis of the Zurich data suggests the converse for philosophers: Their high rates of charity reflect a fact about who chooses philosophy rather than the power of philosophical instruction.
So here are the charity rates for non-philosophers, by year of schooling:
First year: 15%
Second year: 15%
Third year: 14%
Fourth year: 13%
And for philosophers (looking at 1172 student semesters total):
First year: 26%
Second year: 27%
Third year: 21%
Fourth year: 24%
So it looks like philosophers' donation rates are flat to declining, not increasing. Given the moderate-sized data set, the slight decline from 1st and 2nd to 3rd and 4th years is not statistically significant (though given the almost 70,000 data points the smaller decline among non-philosophers is statistically significant).
One reaction some people have had to my work with Josh Rust on the moral behavior of ethics professors (e.g., here and here) is this: Although some professional training in the humanities is morally improving, one reaches a ceiling in one's undergraduate education after which further training isn't morally improving -- and philosophers, or humanities professors, or professors in general, have pretty much all hit that ceiling. That ceiling effect, the objection goes, rather than the failure of ethics courses to alter real-world behavior, explains Josh's and my finding that ethicists behave on average no better than do other types of professors. (Eddy Nahmias might suggest something like this in his critical commentary on one of Josh's and my papers next week at the Society for Philosophy and Psychology.)
I don't pretend that this is compelling evidence against that position. But it does seem to be a wee bit of evidence against that position.