An agent-based model of innovation diffusion: network structure and coexistence under different information regimes

The paper analyzes how the structure of social networks affects innovation diffusion and competition under different information regimes. Diffusion is modeled as the result of idiosyncratic adoption thresholds, local network effects and information diffusion (broadcasting and demonstration effect from previous adopters). A high social cohesion decreases the probability of one innovation cornering the market. Nonetheless, with imperfect information, in small-world networks the higher speed of diffusion produced by the low average distance increases this probability. A low social cohesion also increases the probability of falling into traps of under-adoption. However, such probability is significantly lower with imperfect information, because such regime is characterized by higher levels of market concentrations and this reduces the frictions due to the coexistence of non-compatible product innovations.     

The Credit Channel at Work: Lessons from the Financial Crisis in Korea

We demonstrate that the credit channel of transmission of monetary/financial shocks appears to have aggravated Korea's economic crisis. We use micro-data gathered at the individual bank level to identify this channel of transmission. Our major findings are as follows: i) consistent with banks' autonomous retrenchment in loan supply, monetary tightening broadens the spread between marginal bank lending rates and corporate commercial paper rates; ii) credit limits on overdrafts – arguably a proxy identifying shifts in loan supply – react negatively to the monetary squeeze; iii) large negative capital shocks induce banks to disproportionately slow-down both lending and deposit taking and to disproportionately raise their lending rates. Our findings lend unequivocal support to the hypothesis that banks' autonomous contraction restricted the availability of credit and magnified the increase in its cost. In turn, this compounded the Korean crisis by aggravating liquidity constraints for the vast majority of agents who rely only on bank credit as an external source of funds.     

Partnership,reciprocity and team design

This paper studies the effect of intention-based reciprocity preferences on the free-riding problem arising in partnerships. Our results suggest a tendency of efficient partnerships to consist of members whose sensitivity to reciprocity is – individually or jointly – sufficiently high. Sufficient conditions for the implementation of the efficient strategy profile require a reciprocity-based sharing rule so that each partner gets a fraction of the output, which is a percentage of his own sensitivity to reciprocity with respect to the overall sensitivity in the team. Finally, we introduce the concept of psychological strong Nash equilibrium and show that it allows for the unique and collusion-proof implementation of the efficient strategy profile.     

Micro versus macro cointegration in heterogeneous panels

We consider the issue of cross-sectional aggregation in nonstationary and heterogeneous panels where each unit cointegrates. We derive asymptotic properties of the aggregate estimate, and necessary and sufficient conditions for cointegration to hold in the aggregate relationship. We then analyze the case when cointegration does not carry through the aggregation process, and we investigate whether the violation of the formal conditions for perfect aggregation can still lead to an aggregate equation that is observationally equivalent to a cointegrated relationship. We derive a measure of the degree of noncointegration of the aggregate relationship and we explore its asymptotic properties. We propose a valid bootstrap approximation of the test. A Monte Carlo exercise evaluates size and power properties of the bootstrap test.     

Strategic Interactions and Contagion Effects under Monetary Unions

This paper applies game theory and a cost‐benefit analysis to study voluntary exits and contagion effects in countries joined to a monetary union. The paper looks at two non‐core or periphery countries of a large union and examines the role of structural asymmetries and strategic interactions as determinants of equilibrium outcomes, following both country‐specific and common shocks. The paper finds that under almost symmetry between countries, country‐specific shocks are never associated with multiple equilibria and, if large enough, can spread to other countries leading to contagion. By contrast, common shocks are seen to sustain multiple equilibria if almost‐symmetric countries are considered and to have implications similar to those found in the country‐specific case if large structural asymmetries are admitted.