* Accepted for publication in the Artificial Intelligence Journal. This
paper is an extended version of our paper arXiv:2006.13699: we added a
Bayesian-optimal baseline (in addition to the group-oblivious baseline) and
generalized the model by assuming a group-dependent distribution of quality
and an implicit bias; but we removed the part on two-stage selection Access Paper or Ask Questions
* 23 pages, 14 figures. Accepted for publication in the 33rd Conference
on Neural Information Processing Systems (NeurIPS 2019), Vancouver, Canada Access Paper or Ask Questions