Estimating Schedule Estimating Schedule DurationsDurationsUsing MS Project PERT Analysis Tool

Presented by Harry SmithMPUG St. Louis Chapter MemberFebruary 9, 2011

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AgendaAgendaWhat is PERT?Estimating Industry Best

PracticesProject Management ScenarioChallenges Opportunities for improvement PERT Analysis tool demoQuestions

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PERTPERT

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Some Industry Best Some Industry Best PracticesPracticesMultiple 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

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Estimate AttributesEstimate Attributes

Exact-estimate is an oxymoron

Realistic estimates must be:

◦Specific

◦Repeatable

◦Defendable

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Estimating InputsEstimating InputsSubject 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

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Project Management Project Management ScenarioScenario

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

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ChallengesChallengesSchedule 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.

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Opportunity for Opportunity for ImprovementImprovementPost-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.

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MS Project and PERTMS Project and PERT Getting started – activate the PERT Analysis toolbar

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MS Project and PERTMS Project and PERT Click on PERT entry sheet toolbar icon Click on PERT Entry Form icon and enter values

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MS Project and PERTMS Project and PERTClick on the PERT weighting icon to set

weighting values

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MS Project and PERTMS Project and PERTOn 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

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MS Project and PERTMS Project and PERTAdding a text field for comments

allows you to document any assumptions that were used to come up with values.◦Remember specific, repeatable, and

defendable

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QuestionsQuestions

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PDU for Members & PDU for Members & Guests:Guests:PDU activity code is:

mpugstlouis020911.

PDUs can be claimed under category 3 on the PMI website.

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Contact info: Harry Smith email:

harry.l.smith@frb.stls.org