We estimate the effect of a marginal personal solicitation after receiving two to four non-personal solicitations using observational data on alumni giving at an anonymous research university, which we refer to as Anon U. At Anon U, volunteers use lists provided by the Development Office to telephone classmates and solicit them for donations. The names on these lists are always in alphabetical order. The volunteers who do the soliciting often run out of time before they reach the end of their lists. These observations suggest a simple strategy for testing whether personal solicitation matters, viz., examine whether alumni with names toward the end of the alphabet are less likely to give than alumni with names toward the beginning, ceteris paribus. If so, then a marginal personal solicitation matters.
