Papers and other resources analyzing data about MathOVerflow

Let us collect here resources which analyze various aspects of MO.

• Montoya L.V., Ma A., Mondragón R.J. (2013) Social Achievement and Centrality in MathOverflow. https://doi.org/10.1007/978-3-642-36844-8_3. This paper analyses mainly stuff related to users and interactions between them.
• Ursula Martin, Alison Pease: What does mathoverflow tell us about the production of mathematics? https://arxiv.org/abs/1305.0904. The authors study a sample of questions on MO, categorize them into various types and look at percentage answered. Ass Gerry Myerson pointed out, this paper is discussed in more detail in François G. Dorais' answer to Is MO connected?