IV regressions without instruments (technical)

Arthur Lewbel published a very interesting paper back in 2012 in the Journal of Business & Economic Statistics (ungated version here). The paper attracted quite some attention because it lays out a method to do two-stage least squares regressions (in order to identify causal effects) without the need for an outisde instrumental variable. Continue reading IV regressions without instruments (technical)

Econometrics: When Everybody is Different

Nowadays everybody is talking about heterogeneous treatment effects. That is, response to an economic stimulus that varies across individuals in a population. However, so far the discussion was concentrated on the instrumental variable setting where a randomized (natural or administered) experiment affects the treatment status of a so-called complier population. An average of the individual treatment effects can only be estimated for this group of compliers. Instead, for the always and never-takers we cannot say anything. But if individual treatment responses are different for everybody in the population, how can we be sure that what we’re estimating for the compliers is representative for the whole population? Continue reading Econometrics: When Everybody is Different

Successfully Mastering Econometrics

Because I’m currently sitting in the same lecture room in Strasbourg as Steve Pischke and yet another paper on labor markets is presented, I feel inspired to comment on the newest Angrist and Pischke piece on econometrics education. Furthermore, my own graduation doesn’t lie too much in the past, so I might still be part of the target group for an improved coursework in quantitative methods. Continue reading Successfully Mastering Econometrics