How to define generational cohorts? The guys from US Today came up with this "generational quiz". It takes just 5 quick questions and it's pretty good (although I'm not sure if its going to help you with your next paper).
"The year you were born partly determines what generation you belong to, but so do your cultural experiences." It identifies 6 different generations: G.I, Silent, Boomer, 'X' (a.k.a. Savvy), Milenial and 'Z'.
ps. I would belong to the Milenial Generation because of my birth year... but it looks like I'm a 'X' according to the quiz result....