I understand that some attributes of God are said to be communicable, meaning that they can, in some measure, be attributes of men as well. For example, God's holiness is said to be communicable because our holiness is derived from his, as in Lev 11:45 "Be holy, for I am holy." (ESV). God's aseity, on the other hand, could not be attributed to humans, as we are created by him.
Many other attributes, however, seem to be more of a gray area for me. For example, one might mark "knowledge" as communicable, or perhaps omniscience as incommunicable. How does one determine whether an attribute of God is communicable or incommunicable?