摘要:We propose a simple mechanism that might improve voluntary contributions topublic goods. Using a laboratory experiment we analyze how bundling public withprivate goods affects individuals’ valuations for both goods. In the experiment,subjects may purchase a private and a public good either separately or in the formof a bundle. The data show superadditivity for bundles of public and private goods,i.e., the willingness to pay for the bundle exceeds the willingness to pay for the twoseparate goods. In contrast, we find no superadditivity in control treatments withonly private goods. We discuss several behavioral concepts which are in line withour results as well as implications for fundraisers and firms.