there's nothing necessarily wrong with this strategy.   the only question for you is whether those matches are really sufficiently equivalent.  matching different years means that for sure there will be some differences (even if only the last digit of the year!), but you're going to need to decide whether those make a difference in your analysis and the effect of that on the outcome is important enough.
Gary
--
Gary King - Albert J. Weatherhead III University Professor - Director, IQSS - Harvard University
GKing.Harvard.edu - King@Harvard.edu - @kinggary - 617-500-7570 - Asst 495-9271 - Fax 812-8581



On Wed, Aug 24, 2011 at 5:44 PM, Nel Dutt <nilanjana.dutt@duke.edu> wrote:

Hi all,

 

I am using CEM on a panel dataset with the k2k option.  I am currently matching observations by year (and a few other covariates).  I was wondering if there are any econometric problems while running regressions (post matching) with a matched sample which contains the following situation:

in year t observation_1 is matched with observation_2, but in year t+1 observation_1 is matched with observation_3.  That is, in different years the same firm is matched with different firms.

 

Thanks,

Nel