747.2
Mobile Social Dilemmas in an Experiment: Mobility Accelerates the Cycle, but Does Not Change Cooperation
This paper sheds light on the role of mobility on cyclic processes in mobile social dilemmas. Olson argues that rational actors will free-ride in large groups. Erhart and Keser’s experiment revealed that people formed clockwise cycles of group size and cooperation when they can change groups. But they did not compare various levels of mobility. Thus, our research question is how mobility affects the cycle and the cooperative behaviors.
2. Methods
We conducted a laboratory experiment (with 168 participants in 40 groups in 10 sessions). Three conditions (treatments) were introduced (immobile, high mobility costs, and low mobility costs conditions).
3. Results
We show the following findings. (i) Mobility did not change effects of size on cooperation (N=339 group-rounds). (ii) Still, mobility accelerated effects of cooperation on size (N=360 group-rounds). As people moved more easily, cooperative groups were more likely to expand. (iii) As a result, intergroup mobility accelerated the cycle (N=40 groups). Groups rotated faster when people moved more easily. (iv) However, mobility did not raise nor decline cooperation levels (N=40 groups).
4. Conclusion
We observed negative effects of size on cooperation. This was consistent with the literature, both on mobile and immobile social dilemmas. We observed cyclic dynamics. This reconfirmed Ehrhart and Keser. We observed identical cooperation at various mobility levels. This was inconsistent with Tieboutʼs prospect. The literature overlooked that free-riders can invade cooperative groups. To foster cooperation among rational actors, first increase mobility to free cooperators. Then, restrict mobility to exclude free-riders.