  While modeling the relationships between evidence and hypotheses, simple graphical patterns (called idioms) are often used. Complex graphical models can be constructed by combining these basic patterns in a modular way. General methods for constructing Bayesian networks are discussed in (Neil, Fenton, and Nielson 2000;   Hepler, Dawid, and Leucari 2007) and general idioms are discussed in (Fenton, Neil, and Lagnado 2013). A few of the basic idioms are illustrated below.