I spoke to someone there, and also researched online. You only choose between a thesis, coursework and a research paper by submitting a written form by early February of your first year of your Master's degree. One must also maintain an A- average if one wishes to undertake the thesis route.
Here is the breakdown:
-5.0 credits required to graduate
-1.0 mandatory credits, includes intro course and an economics course based on your choosen cluster.
-Then one chooses between a thesis (2.0 credits), a research paper (1.0), or just full course work (4.0).
-From the remaining credits for course work, one can choose 1.5 of those credits outside your own cluster, from, say, history or political science.
Hope this helps and good luck .
-CC
P.S.
Personally, if you're interested, I'm aiming for the thesis as I would like to do my PhD afterwards .