Martinsson, PeterVillegas-Palacio, ClaraWollbrant, Conny2009-08-052009-08-052009-08-051403-2465http://hdl.handle.net/2077/20787In contrast to previous studies on cross-group comparisons of conditional cooperation, this study keeps cross- and within-country dimensions constant. The results reveal significantly different cooperation behavior between social groups in the same location.engConditional cooperationexperimentpublic goodssocial groupText