The Complexity of Finding Effectors

Laurent Bulteau (1) , Stefan Fafianie (1) , Vincent Froese (1) , Rolf Niedermeier (1) , Nimrod Talmon (1)

1 SWT - TUB - Department of Software Engineering and Theoretical Computer Science

The NP-hard Effectors problem on directed graphs is motivated by applications in network mining, particularly concerning the analysis of (random) information-propagation processes. In the corresponding model the arcs carry probabilities and there is a probabilistic diffusion process activating nodes by neighboring activated nodes with probabilities as specified by the arcs. The point is to explain a given network activation state best possible using a minimum number of " effector nodes " ; these are selected before the activation process starts. We complement and extend previous work from the data mining community by a more thorough computational complexity analysis of Effec-tors, identifying both tractable and intractable cases. To this end, we also exploit a parameterization measuring the " degree of randomness " (the number of 'really' probabilistic arcs) which might prove useful for analyzing other probabilistic network diffusion problems.

Domaines: Algorithme et structure de données [cs.DS]; Complexité [cs.CC]

Laurent Bulteau, Stefan Fafianie, Vincent Froese, Rolf Niedermeier, Nimrod Talmon. The Complexity of Finding Effectors. TAMC, 2015, Singapore, China. ⟨10.1007/978-3-319-17142-5_20⟩. ⟨hal-01260613⟩