In November 2001, 5,558 readers of the German weekly Die Zeit participated in a three-person ultimatum experiment involving a proposer X, a responder Y, and a dummy Z (Guth and van Damme, 1998). A proposal is a vector (x,y,z) with x + y + z = DM 1,200, and x in {0, 200, 400, 600, 800, 1000}, and...

On 11 May 2001, readers of the Berliner Zeitung were invited to participate in an ultimatum bargaining experiment played in the strategy vector mode: each participant chooses not only how much (s)he demands of the DM1,000 pie but also which of the nine possible offers of DM100, 200,..., 900...