5 papers
Efficient Algorithms for Influence Maximization in General Models and Observed Cascades
Fabian Spaeh, Themistoklis Haris, Alina Ene +1
We study influence maximization in general stochastic models, the observed cascades model, and the independent cascade (IC) model. For general stochastic models with only black-box…
Query Suggestion for Retrieval-Augmented Generation via Dynamic In-Context Learning
Fabian Spaeh, Tianyi Chen, Chen-Hao Chiang +1
Retrieval-augmented generation with tool-calling agents (agentic RAG) has become increasingly powerful in understanding, processing, and responding to user queries. However, the sc…
Estimating Hitting Times Locally At Scale
Themistoklis Haris, Fabian Spaeh, Spyros Dragazis +1
Hitting times provide a fundamental measure of distance in random processes, quantifying the expected number of steps for a random walk starting at node to reach node . They…
An Asymptotically Optimal Approximation Algorithm for Multiobjective Submodular Maximization at Scale
Fabian Spaeh, Atsushi Miyauchi
Maximizing a single submodular set function subject to a cardinality constraint is a well-studied and central topic in combinatorial optimization. However, finding a set that maxim…
Countering Election Sway: Strategic Algorithms in Friedkin-Johnsen Dynamics
Dragos Ristache, Fabian Spaeh, Charalampos E. Tsourakakis
Social influence profoundly impacts individual choices and collective behaviors in politics. In this work, driven by the goal of protecting elections from improper influence, we co…