I would love to first see a technical definition of fairness from EU that can be used to evaluate algorithms. That is a non-trivial detail often overlooked from these discussions.
> 1. Very large online platforms that use recommender systems shall set out in their terms and conditions, in a clear, accessible and easily comprehensible manner, the main parameters used in their recommender systems, as well as any options for the recipients of the service to modify or influence those main parameters that they may have made available, including at least one option which is not based on profiling, within the meaning of Article 4 (4) of Regulation (EU) 2016/679.
> 2. Where several options are available pursuant to paragraph 1, very large online platforms shall provide an easily accessible functionality on their online interface allowing the recipient of the service to select and to modify at any time their preferred option for each of the recommender systems that determines the relative order of information presented to them.
Not technical, but fairness is the opposite of "our algorithm is so complicated that we can't prevent it from penalizing you even if you are not at fault. Unless you reach the top of HN, in which case we will manually intervene to fix things."
> Article 29 Recommender systems
> 1. Very large online platforms that use recommender systems shall set out in their terms and conditions, in a clear, accessible and easily comprehensible manner, the main parameters used in their recommender systems, as well as any options for the recipients of the service to modify or influence those main parameters that they may have made available, including at least one option which is not based on profiling, within the meaning of Article 4 (4) of Regulation (EU) 2016/679.
> 2. Where several options are available pursuant to paragraph 1, very large online platforms shall provide an easily accessible functionality on their online interface allowing the recipient of the service to select and to modify at any time their preferred option for each of the recommender systems that determines the relative order of information presented to them.