The following graphs provide data on various types of interactions Levin has with Gilley in A New Life. 

Overall trends are apparent in Levin's interactions with Gilley; Most interactions seem to consist of Gilley giving information largely unsolicited, which (at least partially) explains his dominating presence in the novel.

Request dynamics offer a lot to work with. For example, Gilley appears to obey Levin's requests a fair amount in the middle of the novel, but not in the beginning or end (where he actually tends to refuse quite frequently). Levin, meanwhile, appears to have a fairly equitable spread between refusal and aquiescence through the graph.

This visualization shows that Levin blackmails Gilley approximately three-quarters through the novel, but in the novel's final moments both characters use blackmail (as a manifestation of a power struggle) with each other. (See: Because I can)

Both characters attempt to hide information from each other, though Levin moreso than Gilley (especially in the novel's second half). Perhaps this is a manifestation of the power dynamics in the novel; Levin, as the subordinate, is less likely to be forthcoming (especially once he does things that usurp traditional power structures, such as have an affair with Pauline).

Unsurprisingly, Gilley gives Levin much more information than Levin gives Gilley within their interactions. The graph demonstrates that their exchanges are short but punctuated by intense floods of information (mostly in Levin's direction).

Not only does Gilley give more information than Levin; he also asks for information more than Levin as well. This helps support the idea that most of Gilley/Levin interactions are carried primarily by Gilley, and that Levin is more a passive participant than an eager actor. However, the novel's conclusion is of particular interest; Levin's final exchanges with Gilley show them asking for information from each other in fairly equitable amounts. Perhaps the revealing of Levin's affair allowed both characters to break down their facades and approach each other honestly (albeit resentfully).