Efficient Online Learning of Optimal Rankings: Dimensionality Reduction via Gradient Descent
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We consider a natural model of online preference aggregation, where sets of preferred items $R_1, R_2, ldots, R_t$ along with a demand for $k_t$ items in each $R_t$, appear online. Without prior knowledge of $(R_t, k_t)$, the learner maintains a ranking $pi_t$ aiming that at least $k_t$ items from $R_t$ appear high in $pi_t$...
This is a fundamental problem in preference aggregation with applications to, e.g., ordering product or news items in web pages based on user scrolling and click patterns. The widely studied Generalized Min-Sum-Set-Cover (GMSSC) problem serves as a formal model for the setting