ABSTRACT
This study assessed the effects of individual and common resources availability in choosing individual or shared contingencies in a partial altruism situation. The experimental situation consisted in placing blocks on three different boards. Sixteen elementary school children were assigned to eight dyads, divided in two groups of four dyads each. Groups differed in the sequence of exposure to individual or common resources availability. Participants could observe their peers' performance and place blocks in their own board obtaining points only for themselves, could place blocks in the common board obtaining equal points for their peers and themselves, and/or could place blocks in the peers' board providing points only for their peers. Findings suggest that initial exposure to individual or to common resources availability affects the choice for individual or shared contingencies, respectively. Results are discussed in terms of interactions between individuals related to exchange contingencies and reciprocity interactions.