no code implementations • 26 May 2022 • Alexia Atsidakou, Constantine Caramanis, Evangelia Gergatsouli, Orestis Papadigenopoulos, Christos Tzamos
Pandora's Box is a fundamental stochastic optimization problem, where the decision-maker must find a good alternative while minimizing the search cost of exploring the value of each alternative.
no code implementations • 10 Feb 2022 • Evangelia Gergatsouli, Christos Tzamos
In Pandora's Box, we are presented with $n$ boxes, each containing an unknown value and the goal is to open the boxes in some order to minimize the sum of the search cost and the smallest value found.
no code implementations • 30 Aug 2021 • Shuchi Chawla, Evangelia Gergatsouli, Jeremy McMahan, Christos Tzamos
For distributions of support $m$, UDT admits a $\log m$ approximation, and while a constant factor approximation in polynomial time is a long-standing open problem, constant factor approximations are achievable in subexponential time (arXiv:1906. 11385).
1 code implementation • 17 Jul 2021 • Dimitris Fotakis, Evangelia Gergatsouli, Themis Gouleakis, Nikolas Patris
We prove that the competitive ratio decreases smoothly from sublogarithmic in the number of demands to constant, as the error, i. e., the total distance of the predicted locations to the optimal facility locations, decreases towards zero.
no code implementations • ICML 2020 • Evangelia Gergatsouli, Brendan Lucier, Christos Tzamos
In this work we develop algorithms that are able to restore monotonicity in the parameters of interest.