Business cycle synchronization in a simple Keynesian macro-model with socially transmitted economic sentiment and international sentiment spill-over

We propose a simple Keynesian business cycle model in which national income expectations of heterogeneous interacting investors affect their investment decisions. The investors' expectation formation is influenced by their sentiment: investors who hold optimistic views about the future state of the economy expect a higher aggregate demand in the following period and thus invest more than pessimistic investors. The investors' sentiment is, in turn, subject to socio-economic interactions. Simulations show that our model has the potential to generate complex business cycle dynamics. Based on that framework, we provide a three-country model of business cycle synchronization in which spill-over effects on the level of sentiment synchronize national cycles, provided that investors believe that the economies are indeed coupled.