1. A computer method, comprising carrying out operations on a computer, the operations comprising: maintaining machine readable embodiments on a medium of a bipartite graph and a tripartite graph, the tripartite graph comprising a first plurality of nodes corresponding to labeled and unlabeled examples from source and target domains; a second plurality of nodes corresponding to features; and a first plurality of edges connecting the nodes corresponding to the features to the nodes corresponding to the examples according to whether the features appear in the examples or not; the bipartite graph comprising the first plurality of nodes corresponding to the examples; and a second plurality of edges connecting the examples, the edges being associated with indications that indicate whether connected examples are in a same domain or not; deriving labels for at least one target domain based on the tripartite and bipartite graphs; and presenting an embodiment of the labels as a result, wherein said deriving comprises: formulating an objective function based on said bipartite and tripartite graphs, said objective function encompassing smoothness and consistency constraints and providing label information in the target domain at least responsive to label information in the source domain; applying the objective function to the all examples, whether labeled or unlabeled, and all features in order to obtain at least one result relative to the unlabeled examples; minimizing the objective function to yield a label function; and providing output labels responsive to the label function.