I was reading about the "cohort effect" and wanted to know more info, and was surprised that Wikipedia didn't have an article about it.  After a long search and after writing a stub - I finally found the article on a "cohort study" which is an method by which the cohort effect may be scientifically observed.  

 I thought it was a good idea to leave something about this effect - with a link to the method of studying it - in case someone was looking. 

 I'm not sure it makes sense to have it as its own article though.  Probably one should link to the other - with a mention in "cohort study" about the "cohort effect" - so searchers might find it.