Identification in a nutshell Key identifying restriction(the mean consumption profile under the no-retirement alternative is smooth enough at zero) E{x|S=0}=E{|S=0 The result rests upon a weak regularity condition: if none of the heads were to retire no discontinuity in household consumption would take place at the time they become eligible (i.e. at S=0) see Hahn et al. (2001)and Battistin and Rettore( 2006) This amounts to assuming that any idiosyncratic shocks relevant to the retirement choice and correlated with Yo(e.g. health shocks) do not occur selectively at either side of the eligibility thresholdKey identifying restriction (the mean consumption profile under the no-retirement alternative is smooth enough at zero): The result rests upon a weak regularity condition: if none of the heads were to retire no discontinuity in household consumption would take place at the time they become eligible (i.e. at S*=0) – see Hahn et al. (2001) and Battistin and Rettore (2006). This amounts to assuming that any idiosyncratic shocks relevant to the retirement choice and correlated with Y0 (e.g. health shocks) do not occur selectively at either side of the eligibility threshold.     * * 0 0 E Y S E Y S | 0 | 0 + − = = = Identification in a nutshell