Consider the following experiment involving door-to-door fundraising for a charity.Fifteen households are randomly assigned to each of three groups with the constraint that each group consists of 5 households.One group of participants was first asked to sign a petition (The charity is well-respected by everyone and addresses non-controversial problems and issues.) before being asked to make a donation to the charity (This is the foot-in-the-door condition).Participants in a control group were not asked to sign a petition before making a donation. Participants in the door-in-the-face group were initially asked to donate $500 to the charity.All of the participants in this group refused this first request.They were then asked to donate any amount they could, however small.

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