The Online Min-Sum Set Cover Problem

@article{Fotakis2020TheOM,
  title={The Online Min-Sum Set Cover Problem},
  author={Dimitris Fotakis and Loukas Kavouras and Grigorios Koumoutsos and Stratis Skoulakis and Manolis Vardas},
  journal={ArXiv},
  year={2020},
  volume={abs/2003.02161}
}
We consider the online Min-Sum Set Cover (MSSC), a natural and intriguing generalization of the classical list update problem. In Online MSSC, the algorithm maintains a permutation on $n$ elements based on subsets $S_1, S_2, \ldots$ arriving online. The algorithm serves each set $S_t$ upon arrival, using its current permutation $\pi_{t}$, incurring an access cost equal to the position of the first element of $S_t$ in $\pi_{t}$. Then, the algorithm may update its permutation to $\pi_{t+1… 

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