As Nils (and Carla) noted above, the paper clearly contains plagiarism. It includes verbatim sections from a paper by Dahlin (http://garrido.pe/lecturasydocumentos/DAHLIN%20(2008)%20the%20impact%20of%20education%20on%20eco%20growth.pdf) without attribution. Specifically, the portion starting on the bottom of page 2189 (after the “i.e.”) is directly from the Dahlin paper (starting on page 9). Dahlin isn’t cited anywhere, nor is Wagstaff, who is Dahlin’s source on the Mincerian equation.
Interestingly, and unsurprisingly, they did a poor job of copying the equation — converting tau’s to t’s in the first equation, but not the second, and then continuing to refer to tau in the following paragraph. They also messed up the second summation in the first equation, having it start with T = t-1, instead of t = s+1. It’s understandable how a reviewer might miss the mistake in the equation around the t-1 vs. s+1, but the capital T is completely unused and unreferenced, so that ought to have been picked up.
The long passages quoted verbatim from other papers without quotes, but cited, might be forgivable (although it’s still pretty sketchy); however, the outright copying from Dahlin without citation is plagiarism, pure and simple.
