19. The method of claim 14 wherein said background distribution is determined through a process comprising: i) providing two sets of MI values: {MI i }, the set of all mutual information values for gene i, in row or column i of said matrix; and {MI j }, the set of all mutual information values for gene j, in row or column j of said matrix; and ii) approximating a marginal probability density function g i (MI i ) and g j (MI i ) for MI i and MI j using an analytical function, and combining the probability density functions using a composite analytical function.
14. The method of claim 13 wherein said step of applying a background correction comprises the steps of estimating a likelihood of the mutual information score, MI, for a given pair of genes, genes i and j, representing row or column i and row or column j of said adjacency matrix, by comparing the mutual information score, MI ij , for that pair to a background distribution of mutual information values.