Natural Experiment Data

This is parsed data from https://archive.org/details/stackexchange, where we use code from https://github.com/KeithBurghardt/Stack-Exchange-User-Behavior to determine how users choose answers to questions on Stack Exchange given answer positions. Included in this data is a natural experiment, in which answers with the same score were ordered oldest-first before August, 2009, but were ordered at random after August, 2009. We use code in https://github.com/KeithBurghardt/CognitiveBiasesQuestion-AnsweringSystems to parse this data and find that this change implies users have a strong preference for answers seen first. This preference increases with the number of answers such that moving the rank of an answer by 1 position has nearly no effect when two answers are visible, but increases the probability an answer is voted up by 87% when 15 answers are visible!