Network effects on strategic interactions: A laboratory approach

We examine the effect of interaction structure (network) on two classes of collective activities, herding and shirking, respectively referring to the situation where a player’s incentive to take a certain action increases and decreases if more of her network neighbors follow the same action. In our experiment, we find that subjects do not act according to theoretical equilibrium, and their frequencies of making the socially beneficial choice in herding and shirking games are inversely influenced by the number of network neighbors they have. Moreover, the observed local network effect is stronger in shirking games, while the global network effect is more significantly present in herding games. We explain the behavioral regularities through a hybrid learning model, which extends SEWA learning into a network context. As such, our learning model provides a foundation for the observed dynamics, disequilibrium behavior, as well as the local and global network effects.

我们分别研究了互动结构（网络）对两类集体活动——从众和偷懒的影响，从众是指如果一个参与者的更多网络邻居采取某一行动，该参与者采取相同行动的动机增强的情况，偷懒是指如果一个参与者的更多网络邻居采取某一行动，该参与者采取相同行动的动机减弱的情况。在我们的实验中，我们发现实验对象的行为并不符合理论上的均衡，并且他们在从众和偷懒博弈中做出对社会有益选择的频率受到其网络邻居数量的反向影响。此外，观察到的局部网络效应在偷懒博弈中更强，而全局网络效应在从众博弈中更显著。我们通过一个混合学习模型来解释这些行为规律，该模型将SEWA学习扩展到网络环境中。因此，我们的学习模型为观察到的动态、非均衡行为以及局部和全局网络效应提供了基础。