Amazon created a platform called Mechanical Turk that allows Requesters to create small tasks (Human Intelligence Tasks or HITs) that Workers can perform for an extremely modest fee such as 25 or 50 cents per task.* Because the site can be used to collect survey data, it has become a boon for social scientists interested in an experimental design to test causal mechanisms of interest (see Adam Berinsky's short description here). The advantage of Mechanical Turk is the cost. For a fraction of the expense it costs to field a survey with Knowledge Networks/GfK, Qualtrics, or other survey...