This paper studies the properties of convexity (concavity) and strategic complements (substitutes) in network formation and the implications for the structure of pairwise stable networks. First, different definitions of convexity (concavity) in own links from the literature are put into the...

Stochastic correlation models have become increasingly important in financial markets. In order to be able to price vanilla options in stochastic volatility and correlation models, in this work, we study the extension of the Heston model by imposing stochastic correlations driven by a stochastic...

As the American early exercise results in a free boundary problem, in this article we add a penalty term to obtain a partial differential equation, and we also focus on an improved definition of the penalty term for American options. We replace the constant penalty parameter with a...

In Farrell and Maskin (1989), the authors present sufficient conditions for weakly renegotiation-proof payoffs in their Theorem 1 (p. 332). We show that a step in the proof of this theorem is not correct by giving a counterexample. Nevertheless, the sufficient conditions remain true, and we...