We were hoping you'd ask. The MS has one fundamental goal, which is to equip you with the tools and techniques that are needed for you to become a researcher. The canonical example we have in mind is that of the entering doctoral Ph.D. student, and the program is designed to hone those skills that turn you into a top doctoral student. Those same qualifications will also equip you for a career in research in the tech or finance sector, if that's what you are after. Apart from this, the MS is math-heavy, and we will be looking for students who have a substantial amount of mathematics background, as we've already mentioned. The MS is also an accelerated program that lasts 10 months, starting around mid-July and ending in mid-May the year after.
Although the MA program also requires quantitative courses in its core curriculum, the MA in Economics has broader goals and is a more flexible program. For instance, you have the option to take graduate courses outside the Department, such as in the Stern School of Business (especially Finance), the Mathematics Department (NYU Courant), the NYU Center for Data Science and the Politics Department. A few exceptionally qualified students also take PhD courses in economics. You will not have that flexibility in the MS program. While some of our graduates from the MA program do go on to top-rated doctoral programs in economics, most of our students move into the private sector, including finance, banking and consulting positions, and other students also pursue careers in government and international organizations.
Think of the MA as building more applied, empirical and policy-oriented skills, and the MS as a program for strengthening core, research-related capabilities. But this is only a general rule, and neither program locks you into just one option or the other. For example, students who might initially be less strong in math may use the MA to improve their math background to pursue more advanced study in economics. Similarly, MS students may decide to pursue careers in tech, finance or public policy.
Finally, the MA program moves at a more regular pace and its duration is longer. Students start at the beginning of the fall semester (early September) and complete the program in three or four standard semesters, graduating after 16 months or 21 months, respectively. (Students take a break over the summer between years one and two or may undertake an internship.)
And in case you were wondering, yes, both programs are STEM eligible.
It is imperative to emphasize that the two programs are in no sense "vertically ranked". You are equally valued in each program but will encounter challenges in different dimensions and at a different pace. You CANNOT apply to both programs simultaneously. So please think carefully about which program better serves your particular needs.