Lee, Myoung-Jae - In: Journal of Applied Econometrics 19 (2004) 3, pp. 323-337
In estimating the effect of an ordered treatment τ on a count response y with an observational data where τ is self-selected (not randomized), observed variables x and unobserved variables ϵ can be unbalanced across the control group (τ = 0) and the treatment groups (τ = 1, …, J). While...