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arXiv · 1307.2278

Collective Philanthropy: Describing and Modeling the Ecology of Giving

William L. Gottesman·Andrew James Reagan·Peter Sheridan Dodds
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Abstract

Reflective of income and wealth distributions, philanthropic gifting appears to follow an approximate power-law size distribution as measured by the size of gifts received by individual institutions. We explore the ecology of gifting by analysing data sets of individual gifts for a diverse group of institutions dedicated to education, medicine, art, public support, and religion. We find that the detailed forms of gift-size distributions differ across but are relatively constant within charity categories. We construct a model for how a donor's income affects their giving preferences in different charity categories, offering a mechanistic explanation for variations in institutional gift-size distributions. We discuss how knowledge of gift-sized distributions may be used to assess an institution's gift-giving profile, to help set fundraising goals, and to design an institution-specific giving pyramid.

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William L. Gottesman, Andrew James Reagan, Peter Sheridan Dodds. 2014-05-03. Collective Philanthropy: Describing and Modeling the Ecology of Giving. https://doi.org/10.1371/journal.pone.0098876

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