You  might want to check the research done by Pascerella and Terenzini.
Hope this helps.  Tamara

Realizing the Educational Potential of Residence Halls.  Eric Microfiche
ED375762

Place of Residence and First Year Marks.  ED418671

Enhancing the Educational Impact of Residence Halls.  Journal of College
STudent Development v38 n6 p609-21 Nov-Dec 1997.

How College Affects Students...  ED330287

A Meta-Analysis of the Influence of College Residence Halls on Academic
Performance.  Journal of College STudent Dev.  v30 July 1989 p. 289

Institutional INtegration, Academic Success, and Persistence of
First0Year
Commuter and Resident Students.  Journal of CSD.  v34 Sept. 1993 p. 321

Academic Achievement of Freshmen as a Function of Residence Hall
Housing.
NASPA Journal, v22 n3 p. 22-28.  Win 1985

Books:

Pascarella and Terenzini (1991) How College Affects Students.

Realizing the Educational Potential of Residence Halls (1994).  Eds.
Schroeder, Mable, and Assoc.

1.  Resident g.p.a. vs. non-resident g.p.a.
Over the last 7 years, we have compared resident vs non-residents
among freshmen and sophomore, and it have been consistent that resident
students have higher GPA  and retention rate in general. We never done
the alumni contribution study.

you might want to check out these two:

How College Affects Students--Pascarella and Terenzini
Involving Colleges--George Kuh and editors