re: MBA, MS Economics, PhD Economics programs at LSU

Typically, traditional PhD programs are very restricted in entry. It's partially about the metrics, but it's also about whether the prospective student is a good fit for the program. Many PhD programs off few un-funded spots...ie, they're only offering admission to as many students as can be supported by assistantships or fellowships. It's definitely not a "pay to play" environment at many Research I institutions. Your proposed area of research matters too--if the dept has NO faculty working in the proposed area, they may not admit you.

MBA and MS are different animals. MBA is very much pay to play: if you've got the scores, they're happy to take your money, or some other school with less rigor/less competitive admissions will be happy to take your money. MBAs are seriously devalued these days, so choose w/care.