This paper applies return-on-equity networks to portfolio optimization, integrating DuPont analysis and graph theory. Portfolio diversification is interpreted with the network structure, where an inter-cluster relationship diversifies business models, and an inner-cluster relationship variegates...

The paper proposes a model to investigate the influences of agglomeration on heterogeneous firms' exporting behaviors. In the model, firms are heterogeneous in productivity. Selection effect and agglomeration economies caused by agglomeration increase firms' productivity and decreases industrial...