Abstract: A software and/or hardware facility for graphically displaying schedule uncertainty inherent in projects. In some embodiments, the facility generates uncertainty bars for display to users that express the uncertainty inherent in work items, such as projects and/or tasks. An uncertainty bar can visually indicate the work item's earliest start date, earliest expected finish date, expected finish date, latest expected finish date and latest finish date, as calculated by the facility. For a project that has multiple component tasks, the facility can generate an uncertainty bar for each component task. The facility can also generate an uncertainty bar for the entire project. In some embodiments, the facility generates graphs that display the history of uncertainty for work items.

Abstract: A software and/or hardware facility for managing project schedules having inherent uncertainty. The facility allows users to create hierarchical data structures to model projects and other collective efforts. The hierarchical data structures contain work items that can represent tasks, collections of tasks and collections of collections and tasks. Each work item can have associated with it an estimate provided by a user, such as a ranged estimate of the amount of work remaining before the work item is completed. Based at least in part on the provided estimate, the facility can calculate expected start and finish dates for each work item. By calculating expected start and finish dates for all or most of the work items in a project, the facility is able to calculate an expected end date for the entire project. By basing the calculation on ranged estimates, the facility can account for the uncertainty inherent in projects.