@techreport{BruttelFelgendreherGuethetal.2019,
  type      = {Working Paper},
  author    = {Bruttel, Lisa Verena and Felgendreher, Simon and G{\"u}th, Werner and Hertwig, Ralph},
  title     = {Strategic ignorance in repeated prisoners' dilemma experiments and its effects on the dynamics of voluntary cooperation},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {10},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-43188},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431881},
  pages     = {30},
  year      = {2019},
  abstract  = {Being ignorant of key aspects of a strategic interaction can represent an advantage rather than a handicap. We study one particular context in which ignorance can be beneficial: iterated strategic interactions in which voluntary cooperation may be sustained into the final round if players voluntarily forego knowledge about the time horizon. We experimentally examine this option to remain ignorant about the time horizon in a finitely repeated two-person prisoners' dilemma game. We confirm that pairs without horizon knowledge avoid the drop in cooperation that otherwise occurs toward the end of the game. However, this effect is superposed by cooperation declining more rapidly in pairs without horizon knowledge during the middle phase of the game, especially if players do not know that the other player also wanted to remain ignorant of the time horizon.},
  language  = {en}
}
@techreport{BruttelGuethNithammeretal.2020,
  type      = {Working Paper},
  author    = {Bruttel, Lisa Verena and G{\"u}th, Werner and Nithammer, Juri and Orland, Andreas},
  title     = {Inefficient Cooperation under Stochastic and Strategic Uncertainty},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {20},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-47550},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-475500},
  year      = {2020},
  abstract  = {Stochastic uncertainty can cause difficult coordination problems that may hinder mutually beneficial cooperation. We propose a mechanism of ex-post voluntary transfers designed to circumvent these coordination problems and ask whether it can do so. To test this, we implement a controlled laboratory experiment based on a repeatedly played Ultimatum Game with a stochastic endowment. Contrary to our hypothesis, we find that allowing voluntary transfers does not entail an efficiency increase. We suggest and analyze two main reasons for this finding: First, the stochastic uncertainty forces proposers to accept high strategic uncertainty if they intend to cooperate by claiming a low amount (which many proposers do not). Second, many responders behave only incompletely conditionally cooperative by transferring too little (which hinders cooperation in future periods).},
  language  = {en}
}
@techreport{BruttelGuethHertwigetal.2020,
  type      = {Working Paper},
  author    = {Bruttel, Lisa Verena and G{\"u}th, Werner and Hertwig, Ralph and Orland, Andreas},
  title     = {Do people harness deliberate ignorance to avoid envy and its detrimental effects?},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {17},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-44446},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-444463},
  year      = {2020},
  abstract  = {Envy is an unpleasant emotion. If individuals anticipate that comparing their payoff with the (potentially higher) payoff of others will make them envious, they may want to actively avoid information about other people's payoffs. Given the opportunity to reduce another person's payoff, an individual's envy may trigger behavior that is detrimental to welfare. In this case, if individuals anticipate that they will react in a welfare-reducing way, they may also avoid information about other people's payoffs from the outset. We investigated these two hypotheses using three experiments. We found that 13\% of our potentially envious subjects avoided information when they did not have the opportunity to reduce another participant's payoff. Psychological scales do not explain this behavior. We also found that voluntarily uninformed subjects did neither deduct less of the payoff nor less frequently than subjects who could not avoid the information.},
  language  = {en}
}
@article{BruttelGuethNithammeretal.2022,
  author    = {Bruttel, Lisa Verena and G{\"u}th, Werner and Nithammer, Juri and Orland, Andreas},
  title     = {Inefficient cooperation under stochastic and strategic uncertainty},
  series = {Conflict resolution},
  volume    = {66},
  journal   = {Conflict resolution},
  number    = {4-5},
  publisher = {Sage Publ.},
  address   = {Thousand Oaks},
  issn      = {0022-0027},
  doi       = {10.1177/00220027211066614},
  pages     = {755 -- 782},
  year      = {2022},
  abstract  = {Stochastic uncertainty can cause coordination problems that may hinder mutually beneficial cooperation. We propose a mechanism of ex-post voluntary transfers designed to circumvent these coordination problems and ask whether it can increase efficiency. To test this transfer mechanism, we implement a controlled laboratory experiment based on a repeated Ultimatum Game with a stochastic endowment. Contrary to our hypothesis, we find that allowing voluntary transfers does not lead to an efficiency increase. We suggest and analyze two major reasons for this failure: first, stochastic uncertainty forces proposers intending to cooperate to accept high strategic uncertainty, which many proposers avoid; second, many responders behave only incompletely conditionally cooperatively, which hinders cooperation in future periods.},
  language  = {en}
}