Without any other information, I'm clearly better off going with the A.
Firstly, your opinion that you are "clearly better off" is discrimination. The only information you have (per your design) is that 50% of group B performed lower when they were at a disadvantage (conversely, the other 50% of group B performed as well as group A even though that other 50% were also at a disadvantage - hence, more qualified than group A). Using your self imposed limit on available information, you would be better off selecting the candidate that belonged to group B (50% were effectively equivalent to group A as they performed lower when at disadvantage, and the other 50% were effectively superior to group A as they performed equally to group A even when at disadvantage). If you choose to ignore the existence of that disadvantage then you are correct - but that disadvantage exists.
Secondly, what is the real world example of lacking any further information about a candidate other than the group they belong to (i.e. their race)? And how is selection on that single point of information not inherently racist?
Firstly, your opinion that you are "clearly better off" is discrimination. The only information you have (per your design) is that 50% of group B performed lower when they were at a disadvantage (conversely, the other 50% of group B performed as well as group A even though that other 50% were also at a disadvantage - hence, more qualified than group A). Using your self imposed limit on available information, you would be better off selecting the candidate that belonged to group B (50% were effectively equivalent to group A as they performed lower when at disadvantage, and the other 50% were effectively superior to group A as they performed equally to group A even when at disadvantage). If you choose to ignore the existence of that disadvantage then you are correct - but that disadvantage exists.
Secondly, what is the real world example of lacking any further information about a candidate other than the group they belong to (i.e. their race)? And how is selection on that single point of information not inherently racist?