Computes the enrichment in protein-protein interactions.
Usage
ppi_enrichment(hitList, ppi_network)
Arguments
hitList
sorted list of proteins (from the most significant to the least significant)
ppi_network
an igraph object containing the graph of the protein-protein interaction's network.
Value
enrichment
pvalue that describes the probability to get such a number of interactions by chance
lambda
expected number of interactions
References
Pradines JR, Farutin V, Rowley S, Dancik V. Analyzing protein lists with large networks: edge-count probabilities in random graphs with given expected degrees. J. Comput. Biol. 2005;12:113-128.
Franceschini, A et al. (2013). STRING v9.1: protein-protein interaction networks, with increased coverage and integration. In:Nucleic Acids Res. 2013 Jan;41(Database issue)