Press/Studies How many Mechanical Turk workers are there?

[electrolyte]

"TL;DR: There are about 100K-200K unique workers on Amazon. On average, there are 2K-5K workers active on Amazon at any given time. On average, 50% of the worker population changes within 12-18 months. Workers exhibit widely different patterns of activity, with most workers being active only occasionally, and few workers being very active. Combining these results from Hara et al, we see that MTurk has a yearly transaction volume of a few hundreds of millions of dollars."

Full post with all the details: http://www.behind-the-enemy-lines.com/2018/01/how-many-mechanical-turk-workers-are.html