Government Treasury bills: Very strange things indeed. It's quite a story.
Computational (agent-based) models interpret the first two systems described in Monetary Economics, a book written by and Marc Lavoie (G&L). Agent-based models solve computationally; not as a system of equations. Models must remain consistent with G&L accounting.
View the output of agent-based monetary model simple (ABMSIM).
View an outline of agent-based monetary model portfolio choice (ABMPC).