Before revision:  Our result contrasts with related work by Chernozhukov and Hansen (2005) for thispoint. We also establish identification of the local treatment effects in multi-valued treatment settings and derive the closed-form expressions of the identified treatment effects.
After revision:  Our result contrasts with related work by Chernozhukov and Hansen (2005) with regard to this. In addition, we identify the local treatment effects in multi-valued treatment settings and derive the closed-form expressions of the identified treatment effects.