Targeting Behavior or Intention? Intervention Strategies in Expressed-Private Opinion Dynamics
Exogenous interventions, including economic incentives, can be used to promote behavioral change and the adoption of new products or practices. They may act on different levels, either directly affecting customers' behavior (expressed level) or changing intentions (private level). The key question is which intervention strategy is more effective: targeting the expressed or the private level. Although expressed-private opinion (EPO) models are especially suitable for addressing this problem, they have not yet been used in this context. To fill this gap, we extend previous agent-based EPO models by incorporating exogenous interventions and compare different intervention strategies. We analyze the resulting model using a mean-field approximation, complemented by Monte Carlo simulations on a complete graph. Our results show that there is no universal answer to whether an intervention should target the expressed or the private opinion. The effectiveness of an intervention depends on the adoption level at the moment of its introduction. Interventions acting on the expressed level are more effective when adoption is still low, whereas interventions acting on the private level are more effective when adoption is already high and the goal is to support internal acceptance and reduce dissonance. Moreover, the model shows that high adoption is accompanied by low dissonance between expressed and private opinions, which is consistent with self-congruity theory. This agreement provides theoretical support for the model and strengthens its policy implications.