@techreport{AndresBruttelFriedrichsen2020,
  type      = {Working Paper},
  author    = {Andres, Maximilian and Bruttel, Lisa Verena and Friedrichsen, Jana},
  title     = {Choosing between explicit cartel formation and tacit collusion - An experiment},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {19},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-47388},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-473885},
  pages     = {55},
  year      = {2020},
  abstract  = {Numerous studies investigate which sanctioning institutions prevent cartel formation but little is known as to how these sanctions work. We contribute to understanding the inner workings of cartels by studying experimentally the effect of sanctioning institutions on firms' communication. Using machine learning to organize the chat communication into topics, we find that firms are significantly less likely to communicate explicitly about price fixing when sanctioning institutions are present. At the same time, average prices are lower when communication is less explicit. A mediation analysis suggests that sanctions are effective in hindering cartel formation not only because they introduce a risk of being fined but also by reducing the prevalence of explicit price communication.},
  language  = {en}
}
@techreport{AndresBruttelFriedrichsen2021,
  type      = {Working Paper},
  author    = {Andres, Maximilian and Bruttel, Lisa Verena and Friedrichsen, Jana},
  title     = {The Leniency Rule Revisited: Experiments on Cartel Formation with Open Communication},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {24},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-49169},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-491696},
  pages     = {62},
  year      = {2021},
  abstract  = {The experimental literature on antitrust enforcement provides robust evidence that communication plays an important role for the formation and stability of cartels. We extend these studies through a design that distinguishes between innocuous communication and communication about a cartel, sanctioning only the latter. To this aim, we introduce a participant in the role of the competition authority, who is properly incentivized to judge communication content and price setting behavior of the firms. Using this novel design, we revisit the question whether a leniency rule successfully destabilizes cartels. In contrast to existing experimental studies, we find that a leniency rule does not affect cartelization. We discuss potential explanations for this contrasting result.},
  language  = {en}
}
@article{AndresBruttelFriedrichsen2021,
  author    = {Andres, Maximilian and Bruttel, Lisa and Friedrichsen, Jana},
  title     = {The leniency rule revisited},
  series = {International journal of industrial organization},
  volume    = {76},
  journal   = {International journal of industrial organization},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0167-7187},
  doi       = {10.1016/j.ijindorg.2021.102728},
  year      = {2021},
  abstract  = {The experimental literature on antitrust enforcement provides robust evidence that communication plays an important role for the formation and stability of cartels. We extend these studies through a design that distinguishes between innocuous communication and communication about a cartel, sanctioning only the latter. To this aim, we introduce a participant in the role of the competition authority, who is properly incentivized to judge the communication content and price setting behavior of the firms. Using this novel design, we revisit the question whether a leniency rule successfully destabilizes cartels. In contrast to existing experimental studies, we find that a leniency rule does not affect cartelization. We discuss potential explanations for this contrasting result.},
  language  = {en}
}
@article{AndresBruttelFriedrichsen2022,
  author    = {Andres, Maximilian and Bruttel, Lisa and Friedrichsen, Jana},
  title     = {How communication makes the difference between a cartel and tacit collusion},
  series = {European economic review},
  volume    = {152},
  journal   = {European economic review},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0014-2921},
  doi       = {10.1016/j.euroecorev.2022.104331},
  pages     = {1 -- 18},
  year      = {2022},
  abstract  = {This paper sheds new light on the role of communication for cartel formation. Using machine learning to evaluate free-form chat communication among firms in a laboratory experiment, we identify typical communication patterns for both explicit cartel formation and indirect attempts to collude tacitly. We document that firms are less likely to communicate explicitly about price fixing and more likely to use indirect messages when sanctioning institutions are present. This effect of sanctions on communication reinforces the direct cartel-deterring effect of sanctions as collusion is more difficult to reach and sustain without an explicit agreement. Indirect messages have no, or even a negative, effect on prices.},
  language  = {en}
}
@techreport{AndresBruttelFriedrichsen2022,
  type      = {Working Paper},
  author    = {Andres, Maximilian and Bruttel, Lisa Verena and Friedrichsen, Jana},
  title     = {How communication makes the difference between a cartel and tacit collusion},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-56223},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-562234},
  pages     = {67},
  year      = {2022},
  abstract  = {This paper sheds new light on the role of communication for cartel formation. Using machine learning to evaluate free-form chat communication among firms in a laboratory experiment, we identify typical communication patterns for both explicit cartel formation and indirect attempts to collude tacitly. We document that firms are less likely to communicate explicitly about price fixing and more likely to use indirect messages when sanctioning institutions are present. This effect of sanctions on communication reinforces the direct cartel-deterring effect of sanctions as collusion is more difficult to reach and sustain without an explicit agreement. Indirect messages have no, or even a negative, effect on prices.},
  language  = {en}
}