ABSTRACT
The provision of public goods is a thoroughly examined issue in experimental and environmental economics. Experimental research has highlighted many critical issues affecting the ability of a collective to provide public goods, such as how contributions are affected by the size of the collective (Isaac and Walker, 1988), the returns from the public good (Fisher et al., 1995), punishment and rewards (Fehr and Gächter, 2000; Dickinson, 2001), member heterogeneity (Chan et al., 1999; Cherry et al., 2005), and many others (see Ledyard, 1995, for a review). An area that has received little attention is how individual contributions are affected by the presence of multiple, competing public goods. The lack of attention directed to this issue is surprising considering life outside the laboratory generally has people contemplating a variety of public goods (Cornes and Itaya, 2003), with the alternatives sometimes being diverse (e.g. green energy program, neighborhood clean-up programs, etc.) or quite similar (e.g. three similar land conservation groups seeking your financial support). Consequently, the question arises how the presence of multiple public goods will affect individual contributions, or free riding, in the laboratory.
