160 likes | 172 Views
Estimating Schedule Durations. Using MS Project PERT Analysis Tool. Presented by Harry Smith MPUG St. Louis Chapter Member February 9, 2011. Agenda. What is PERT? Estimating Industry Best Practices Project Management Scenario Challenges Opportunities for improvement
E N D
Estimating Schedule Durations Using MS Project PERT Analysis Tool Presented by Harry Smith MPUG St. Louis Chapter Member February 9, 2011
Agenda • What is PERT? • Estimating Industry Best Practices • Project Management Scenario • Challenges • Opportunities for improvement • PERT Analysis tool demo • Questions
PERT • Program Evaluation and Review Technique • Critical path is calculated based on: • Estimated durations of activities • Links between the activities (predecessor/successor relationships) • Collect a range of estimates using a weighted average for the duration estimates • Optimistic, Most Likely, Pessimistic
Some Industry Best Practices • Multiple estimates (i.e., bottom-up & top down) • Project team members are the best source of task estimates • Leverage tools if possible • Historical data can be very helpful
Estimate Attributes • Exact-estimate is an oxymoron • Realistic estimates must be: • Specific • Repeatable • Defendable
Estimating Inputs • Subject matter experts (SME) have been identified for estimating tasks • The WBS has been defined and converted to schedule tasks/activities • The project task dependencies have been identified • Identify which tasks/activities will be estimated using the PERT analysis tool
Project Management Scenario • Deliver software components for new web-based applications and enhancements to legacy systems • Manage the project cost, schedule, and effort within ± 10% of baseline estimates
Challenges • Schedule delivery dates were fixed by the customer. • Costs were constrained by budget estimates set with very few requirements. • Delivery scope was somewhat flexible. • Historically, estimated project completion dates were not very accurate. • In fact, individual task estimates were not very accurate.
Opportunity for Improvement • Post-project analysis discovered that schedule variances were primarily due to weak task estimates. • Focus on improving estimating procedures and techniques without drastically impacting how long it takes to prepare estimates.
MS Project and PERT • Getting started – activate the PERT Analysis toolbar
MS Project and PERT • Click on PERT entry sheet toolbar icon • Click on PERT Entry Form icon and enter values
MS Project and PERT • Click on the PERT weighting icon to set weighting values
MS Project and PERT • On the PERT toolbar click on the calculation icon to calculate the task average weighted duration • Next go to the duration field and round up or down to whole numbers as appropriate • Tip: When you hit the calculation icon this will not undo like other actions in MS Project
MS Project and PERT • Adding a text field for comments allows you to document any assumptions that were used to come up with values. • Remember specific, repeatable, and defendable
PDU for Members & Guests: • PDU activity code is: mpugstlouis020911. • PDUs can be claimed under category 3 on the PMI website. Contact info: Harry Smith email: harry.l.smith@frb.stls.org