Dieter Wang

This paper revisits the credit spread puzzle for banks from the perspective of information contagion. The puzzle consists of two stylized facts: Structural determinants of credit risk not onlyhave low explanatory power but also fail to capture common factors in the residuals. We reproduce the puzzle for European bank credit spreads and hypothesize that the puzzle exists because structural models ignore contagion effects. We therefore extend the structural approach to include information contagion through bank business model similarities. To capture this channel, we propose an intuitive measure for portfolio overlap and apply it to the complete asset holdings of the largest banks in the Eurozone. Incorporating this unique network information into the structural model increases explanatory power and removes a systemic common factor fromthe residuals. Furthermore, neglecting the network likely overstates the importance of structural determinants.

This paper introduces a Spatial Vector Autoregressive Moving Average (SVARMA) model in which multiple cross-sectional time series are modeled as multivariate, possibly fat-tailed, spatial autoregressive ARMA processes. The estimation requires specifying the cross-sectional spillover channels through spatial weights matrices. the paper explores a kernel method to estimate the network topology based on similarities in the data. It discusses the model and estimation, focusing on a penalized Maximum Likelihood criterion. The empirical performance of the estimator is explored in a simulation study. The model is used to study a spatial time series of pollution and household expenditure data in Indonesia. The analysis finds that the new model improves in terms of implied density, and better neutralizes residual correlations than the VARMA, using fewer parameters. The results suggest that growth in household expenditures precedes pollution reduction, particularly after the expenditures of poorer households increase; that increasing pollution is followed by reduced growth in expenditures, particularly reducing the growth of poorer households; and that there are significant spillovers from bottom-up growth in expenditures. The paper does not find evidence for top-down growth spillovers. Feedback between the identified mechanisms may contribute to pollution-poverty traps and the results imply that pollution damages are economically significant.