Criminal settings: a person can be denied bail if there is a substantial likelihood that he or she will commit another criminal offence. The base rate problem: base rate: represents the percentage of people within a given population who commit a criminal or violent act. In the past many mentally disordered forensic patients were needlessly kept in restrictive institutions based on erroneous judgements of violence risk. Judgment error and biases: the shortcuts people use to help to make decisions are called heuristics, some of these heuristics lead to inaccurate decisions. Illusory correlation: the belief that a correlation exists between two events that in reality are either not correlated or are correlated to a much lesser degree than believed: people tend to be overconfident in their judgments. Judg(cid:373)e(cid:374)t of risk le(cid:448)el is (cid:271)ased o(cid:374) the e(cid:448)aluator"s professio(cid:374)al judgment: violence-risk-assessment approaches have four components.