AACE PSP flashcards
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32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- WBS work package
- The lowest-level WBS element that can be estimated, scheduled, and assigned to a single owner; typically sized 8 to 80 labor hours.
- PERT expected duration
- Weighted average of optimistic, most likely, and pessimistic estimates computed as (O + 4M + P) / 6, used to model duration uncertainty.
- PERT standard deviation
- Measure of duration uncertainty for an activity, computed as (P - O) / 6; path variance is the sum of activity variances along the path.
- Analogous estimating
- Top-down duration or cost estimate based on historical similarity to a comparable past project; fast but less accurate than bottom-up.
- Parametric estimating
- Estimate derived from a unit rate multiplied by a quantity, such as hours per square meter times area; accuracy depends on rate validity.
- Finish-to-start dependency
- Logical relationship where a successor cannot start until its predecessor finishes; the most common dependency type in construction schedules.
- Rolling wave planning
- Progressive elaboration in which near-term work is planned in detail while far-term work remains at summary level and is refined later.
- Project calendar
- Defines working days, shifts, and holidays used to convert activity durations in working days into calendar dates on the schedule.
- Forward pass
- CPM calculation moving left to right: early start equals the maximum early finish of predecessors plus lag; early finish equals early start plus duration.
- Backward pass
- CPM calculation moving right to left: late finish equals the minimum late start of successors minus lag; late start equals late finish minus duration.
- Total float
- Amount of time an activity can be delayed without delaying the project finish; equals late start minus early start or late finish minus early finish.
- Free float
- Time an activity can slip without delaying the early start of any successor; equals the minimum successor early start minus the activity's early finish.
- Critical path
- The longest continuous path through the network; its activities have the least total float, commonly zero, and determine the project duration.
- Negative total float
- Condition where the computed late dates precede early dates, meaning the logic cannot satisfy an imposed finish date without compression or rework.
- Resource leveling
- Resolving resource over-allocation by shifting activity start and finish dates; it may extend the critical path and project finish date.
- Resource smoothing
- Time-limited resource adjustment that uses available float to reduce peaks without moving the project finish date or critical path.
- Lag and lead
- Lag adds wait time between linked activities; lead overlaps them with negative time. Both modify logic and should be used sparingly.
- Schedule constraint
- A date restriction such as start-no-earlier-than or finish-no-later-than that overrides network logic and can distort float calculations.
- Data date
- The status date to which progress is recorded; work before it is actual and work after it is forecast in the update schedule.
- Out-of-sequence progress
- Condition where an activity starts before its predecessor finishes; must be resolved with logic or constraints before the update is valid.
- Remaining duration
- Estimated working time still needed to complete an in-progress activity; combined with actual duration it drives percent complete by duration.
- Finish variance
- Difference between the current forecast finish date and the baseline finish date; negative values indicate the project is ahead of baseline.
- Earned schedule
- Time-based extension of earned value where earned schedule is the baseline date at which planned value equals current earned value.
- SPI(t)
- Schedule performance index for time, computed as earned schedule divided by actual time; values below 1.0 indicate the project is behind schedule.
- Baseline schedule
- The approved, frozen version of the schedule against which progress and change are measured; changes require formal change control.
- Schedule health check
- Audit of logic and structure: no open ends, no negative lags, minimal constraints, reasonable float, and a valid critical path.
- Monte Carlo schedule simulation
- Probabilistic analysis that samples duration distributions across many iterations to produce a distribution of possible project finish dates.
- P80 finish date
- The finish date with an 80 percent probability of being met or beaten in a schedule risk analysis; often used to set contingency.
- Joint confidence level
- Probability that a project will complete at or below a specified cost and schedule target simultaneously, from combined cost-schedule simulation.
- Near-critical path
- A path whose total float is small, often defined as ten days or less, that could become critical if its activities slip.
- Schedule crashing
- Shortening critical-path activity durations by adding resources or overtime, trading increased cost for reduced project duration.
- Fast-tracking
- Compressing the schedule by overlapping activities that were planned in sequence, which increases coordination risk and rework exposure.