Optimism bias
The demonstrated systematic tendency to be over-optimistic about key assumptions, with costs typically higher, benefits typically lower and durations typically longer than anticipated. Defined and required to be explicitly adjusted for in HM Treasury's Green Book, 2026 edition. Estimation bias and its correction are owned by Topic 5.7.
Defined in 2 GAGE programs, which carry 4 distinct definitions of it. The wording above is taught in Certified Enterprise Governance, Risk and Compliance Professional (CEGP).
How each discipline defines it
The same term does different work depending on who is using it. These are the definitions as each program teaches them, unedited.
The demonstrated systematic tendency to be over-optimistic about key assumptions, with costs typically higher, benefits typically lower and durations typically longer than anticipated. Defined and required to be explicitly adjusted for in HM Treasury's Green Book, 2026 edition. Estimation bias and its correction are owned by Topic 5.7.
A well-documented pattern in project estimation, not unique to robotics, in which a project's champion tends to estimate target savings on the optimistic end and its time horizon on the fast end, discussed in Section 3K's Breakdown 2 as one of the recurring ways scoping degrades inside real organizations.
The systematic tendency for appraisers to be over-optimistic about costs, benefits and duration. The UK Green Book requires an explicit adjustment for it, preferably sized from the organization's own measured history of forecast error.
A well-documented human tendency to underestimate the likelihood of a negative outcome affecting one's own project or effort, even while accurately estimating the base rate of similar outcomes for comparable projects in general (Sharot, 2011).
Terms it appears with
Not an alphabetical neighbourhood: these are the terms taught in the same lessons, ranked by how often they appear together.