Top Ten Behavioral Biases in Project Management: An Overview

Abstract

Behavioral science has witnessed an explosion in the number of biases identified by behavioral scientists, to more than 200 at present. The paper identifies the ten most important behavioral biases for project planning and management. First, we argue it is a mistake to equate behavioral bias with cognitive bias, as is common. Cognitive bias is only half the story; political bias is the other half. Second, we list the top-ten behavioral biases in project management: strategic misrepresentation; optimism and uniqueness bias; the planning fallacy; overconfidence, availability, and hindsight bias; the base-rate fallacy; anchoring; and escalation of commitment. Each bias is defined and its impacts on project management explained, with examples. Third, base-rate neglect is identified as a primary reason projects underperform. This is supported by presentation of the most comprehensive set of base rates that exists in project management scholarship, from 2,062 projects. Finally, recent findings of power-law outcomes in project performance are identified as a possible first stage in discovering a general theory of project management, with more fundamental and more scientific explanations of project outcomes than found in existing theory.

Keywords: Behavioral science, behavioral economics, project management, behavioral bias, cognitive bias, political bias, strategic misrepresentation, optimism bias, uniqueness bias, planning fallacy, overconfidence bias, hindsight bias, availability bias, base-rate fallacy, anchoring, escalation of commitment