Participation in social programs is often misreported in survey data, complicating the estimation of the effects of those programs. Prof. Tchernis analyzed the case of endogenous misreporting. Endogenous misreporting, similarly to endogenous participation, can result in the estimates of the treatment effect having opposite signs from the true effect. He also discusses how to choose identifying variables for misreporting and participation and suggest that researchers draw these data from different data sources. For example, identifying variable for participation can be drawn from the treatment rules data, which identifying variables for the misreporting equation can be drawn from the features or responses to the survey in general, e.g. proportion of non-response by each survey participant.