The information here is outdated.
This project has been published as a Registered Report in *Royal Society Open Science*. Manuscript and materials available at https://osf.io/7vbj9/ .
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Version 2 of analysis plan has a new section with one new analysis (See "competition will increase quantity" section).
Version 3 changed two of the priors for the "competition will increase quantity" section from Gamma(1.5, 0.05) to Gamma(2, 0.05).
Some statistical models in the pilot analysis plan were infeasible given the structure of the data. As such, some analyses of the pilot data and proposed analyses for the registered proposal were substantially modified from those in the pre-registered pilot analysis.