Joskow (1987) examined the importance of specific investments to the contract duration of coal contracts. Since different price-adjust mechanisms are also adopted and provide different incentives during a long-term relationship, this paper examines how the level of specific investments affect...

This paper considers nonparametric identification of nonlinear dynamic models for panel data with unobserved voariates. Including such unobserved covariates may control for both the individual-specific unobserved heterogeneity and the endogeneity of the explanatory variables. Without specifying...