1. BSBPMG503A Manage Project Time 6.4 Estimate Activity Duration The process of approximating the number of work periods needed to complete individual activities with the assigned or estimated resources Previous experience in the type of project and activities being estimated greatly helps with the accuracy of duration estimates Duration is a function of work effort and resources Most project management software can perform this function Occurs during the Planning Phase Adapted from PMBOK 4 th Edition InitiationPlanning ExecutionClose Monitor Control

2. BSBPMG503A Manage Project Time 6.4 Estimate Activity Duration Inputs to Estimate Activity Duration Activity list and attributes Activity Resource requirements and estimates Resource Calendars Project Scope Statement Productivity metrics and estimating data Tools and techniques to Estimate Activity Duration Adapted from PMBOK 4 th Edition Three-Point Estimating Expert Judgement Analogous Estimating Parametric Estimating Reserve Analysis

3. BSBPMG503A Manage Project Time 6.4 Estimate Activity Duration Analogous Estimating Develops duration estimates based on previous projects with similar size, risk and complexity Relies heavily of expert judgement and previous experience Less costly and less time consuming than other methods Least accurate Most common form of duration estimating Parametric Estimating Duration is quantified by multiplying the quantity of work by the labour hours required Relies on published estimating data Common in Construction InitiationPlanning ExecutionClose Monitor Control Adapted from PMBOK 4 th Edition

4. BSBPMG503A Manage Project Time 6.4 Estimate Activity Duration Three-Point Estimates - PERT Calculates the Expected activity duration based on the weighted average of the Most Likely, Optimistic and Pessimistic estimates Often more accurate than other methods and quantified range of uncertainty Reserve Analysis Inclusion of contingency Can be calculated for each activity Can be calculated for entire project Often a percentage based on risk or complexity InitiationPlanning ExecutionClose Monitor Control Adapted from PMBOK 4 th Edition

5. BSBPMG503A Manage Project Time 6.4 Estimate Activity Duration The major output of this process Activity Duration Estimates Draft or High Level Project Duration Estimate Often include some form of range of possible results Most common form of range is plus or minus - eg 2 weeks +/- 2 days – the activity could take between 8 and 12 days 3 weeks +/- 30% - the activity could take between 2 weeks and 4 weeks Adapted from PMBOK 4 th Edition InitiationPlanning ExecutionClose Monitor Control