Headshot of John McCoy


John McCoy

I am a Ph.D. student in the Brain and Cognitive Sciences Department at MIT, where I am co-advised by Drazen Prelec and Josh Tenenbaum. Outside of the BCS Department, I spend about half my time with the Sloan marketing group. Amongst other awards, I am a South African recipient of the International Fulbright Science and Technology Award.

I am interested in the processes underlying human judgment and decision making, and applying our knowledge of such processes to problems in marketing. I use a combination of behavioral experiments and formal modeling, drawing on ideas and techniques from psychology, economics, marketing, Bayesian statistics, and computer science.

Much of my current research focuses on the problem of aggregating judgments from many people, including in situations where the majority may be wrong and the truth may be unverifiable. I work on computational models for solving this problem, and psychological questions inspired by these models.

Crowds, and their wisdom

My collaborators and I have proposed a new solution to extracting wisdom from the crowd: select not the "most popular" answer, but rather the "surprisingly popular" answer. That is, elicit from each respondent both their own answer and their prediction about the answers of others and select the answer which is more popular than the crowd itself predicts. We justify this theoretically, and show that it delivers superior performance across a range of domains.

Prelec, D., Seung, H.S., and McCoy, J. “A solution to the single-question crowd wisdom problem” Nature, 2017, 541, 532-535.

Nature crowd wisdom cover

Representative press:

Wall Street Journal, Bloomberg, Quartz,
MIT news, Scientific American, NPR

In a new paper under submission, we draw on these ideas to develop a statistical model for belief aggregation that operates both on separate and multiple questions, and additionally infers respondent expertise.

A selection of other ongoing projects in this space, with numerous collaborators, includes:

Individuals, and their quirks

Ongoing projects on how people make judgments and decisions include:

Graph theory

I have written some mathematics papers:

Henning, M.A., McCoy, J. and Southey, J. "Graphs with maximum size and given paired-domination number" Discrete Applied Mathematics, 2014, 170: 72-82.

Henning, M.A., and McCoy, J. "Which trees have a differentiating-paired dominating set?" Journal of combinatorial optimization, 2011, 22.1: 1-18.

Henning, M.A., and McCoy, J. "Total domination in planar graphs of diameter two" Discrete Mathematics, 2009, 309.21: 6181-6189.

McCoy, J., and Henning, M.A. "Locating and paired-dominating sets in graphs" Discrete Applied Mathematics, 2009, 157.15: 3268-3280.

Dorbec, P., Henning, M. A., & McCoy, J. "Upper total domination versus upper paired-domination" Quaestiones Mathematicae, 2007, 30(1), 1-12.

Apparel for discerning babies

"Always be closing..."