Protein interaction data is subject to experimental error, which means the PINs we work with are noisy observations of the underlying “true”, i.e. biologically relevant, interaction networks. One way of quantifying the reliability of the data is by assigning each interaction a confidence score, such as an estimate of the likelihood that the interaction is “true” given the available evidence. This gives rise to uncertain networks, where the nodes (proteins) are known and the edges (interactions) are “uncertain” and are truly present with probability equal to their score. The classical approach to uncertain networks is to impose a score threshold and convert them to simple deterministic networks. However, the result is very sensitive to the choice of threshold and violates some basic properties implied by the confidence scores. Instead, my research focuses on developing a robust stochastic methodology for extracting information about the structure of the biologically relevant network directly from the scored data.