Project Management CSC 310 Spring 2017 Howard...
Transcript of Project Management CSC 310 Spring 2017 Howard...
ProjectManagementCSC310
Spring2017HowardRosenthal
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No?ce� Thiscourseisbasedonandincludesmaterialfromthetext:EffectiveProjectManagement-Traditional,Agile,Extreme7THEditionAuthors:RobertK.WysockiPublisher:WileyISBN:978-1-118-72916-8,Copyright2014
� Thecourseincludesandinterspersessomematerials,mostoftendiagrams,providedbyMr.Wysocki’sPowerPointslides,atthewebsite:www.wiley.com/go/epm7e
� ItalsoutilizesgeneralinformationandfiguresfromthePMBOK:AGuidetotheProjectManagementBodyofKnowledge(PMBOK5THEdition)Publisher:ProjectManagementInstituteISBN:978-1-935589-67-9,Copyright2013
� Italsoutilizes:AUser’sManualtothePMBOK®Guide—FifthEdition,Snyder,Cynthia
JohnWileyandSons,2013ISBN:978_1_118_43107_8
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LessonGoals
� UnderstandthestepsinvolvedinbuildingascheduleandcreatingnewinformationfortheWBSandWBSDictionary
� Learnhowtodefineactivitiesforaworkpackage� Learnhowtosequenceactivities� Learnmethodsforestimatingresources� Learnsomeofthetoolsusedtoestimateactivitydurations
� Learnhowtodevelopasimpleschedule� UnderstandhowtheoutputsfromthesevariousprocessesareusedtoprogressivelyelaboratetheWBSDictionary
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ProjectManagementProcessGroupsandKnowledgeAreas
4PMBOKTable3-1
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ProjectTimeManagementOverview
5PMBOKFigure6-1
143©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
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.1 Inputs .1 Project management plan .2 Project charter .3 Enterprise environmental factors .4 Organizational process assets
.2 Tools & Techniques .1 Expert judgment .2 Analytical techniques .3 Meetings
.3 Outputs .1 Schedule management plan
Project Time
Management Overview
6.1 Plan Schedule
Management
.1 Inputs .1 Schedule management plan .2 Scope baseline .3 Enterprise environmental factors .4 Organizational process assets
.2 Tools & Techniques .1 Decomposition .2 Rolling wave planning .3 Expert judgment
.3 Outputs .1 Activity list .2 Activity attributes .3 Milestone list
6.2 Define Activities
.1 Inputs .1 Schedule management plan .2 Activity list .3 Activity attributes .4 Milestone list .5 Project scope statement .6 Enterprise environmental factors .7 Organizational process assets
.2 Tools & Techniques .1 Precedence diagramming method (PDM) .2 Dependency determination .3 Leads and lags .3 Outputs .1 Project schedule network diagrams .2 Project documents updates
6.3 Sequence
Activities
.1 Inputs .1 Schedule management plan .2 Activity list .3 Activity attributes .4 Activity resource requirements .5 Resource calendars .6 Project scope statement .7 Risk register .8 Resource breakdown structure .9 Enterprise environmental factors .10 Organizational process assets
.2 Tools & Techniques .1 Expert judgment .2 Analogous estimating .3 Parametric estimating .4 Three-point estimating .5 Group decision-making techniques .6 Reserve analysis
.3 Outputs .1 Activity duration estimates .2 Project documents updates
6.5 Estimate Activity
Durations
.1 Inputs .1 Schedule management plan .2 Activity list .3 Activity attributes .4 Project schedule network diagrams .5 Activity resource requirements .6 Resource calendars .7 Activity duration estimates .8 Project scope statement .9 Risk register .10 Project staff assignments .11 Resource breakdown structure .12 Enterprise environmental factors .13 Organizational process assets
.2 Tools & Techniques .1 Schedule network analysis .2 Critical path method .3 Critical chain method .4 Resource optimization techniques .5 Modeling techniques .6 Leads and lags .7 Schedule compression .8 Scheduling tool
.3 Outputs .1 Schedule baseline .2 Project schedule .3 Schedule data .4 Project calendars .5 Project management plan updates .6 Project documents updates
6.6 Develop Schedule
.1 Inputs .1 Project management plan .2 Project schedule .3 Work performance data .4 Project calendars .5 Schedule data .6 Organizational process assets
.2 Tools & Techniques .1 Performance reviews .2 Project management software .3 Resource optimization techniques .4 Modeling techniques .5 Leads and lags .6 Schedule compression .7 Scheduling tool
.3 Outputs .1 Work performance information .2 Schedule forecasts .3 Change requests .4 Project management plan updates .5 Project documents updates .6 Organizational process assets updates
6.7 Control Schedule
.1 Inputs .1 Schedule management plan .2 Activity list .3 Activity attributes .4 Resource calendars .5 Risk register .6 Activity cost estimates .7 Enterprise environmental factors .8 Organizational process assets
.2 Tools & Techniques .1 Expert judgment .2 Alternative analysis .3 Published estimating data .4 Bottom-up estimating .5 Project management software
.3 Outputs .1 Activity resource requirements .2 Resource breakdown structure .3 Project documents updates
6.4 Estimate Activity
Resources
Figure 6-1. Project Time Management Overview
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
SchedulingOverview
6PMBOKFigure6-2
144 ©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
Examples of Project Schedule Presentations
Network Diagram
Bar ChartActivity List
ProjectSchedule
ScheduleModel
ProjectInformation
SchedulingMethod
SchedulingTool
Output
Generates
Project Specific Data(e.g., WBS, activities,resources, durations,
dependencies, constraints,calendars, milestones
lags, etc.)
For example,CPM
Figure 6-2. Scheduling Overview
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
KeyOutputsofTimeManagementProcessesProcess KeyOutputs
DefineActivities ActivityList
SequenceActivities ProjectScheduleNetworkDiagrams
EstimateActivityResources ActivityresourcerequirementsResourcebreakdownstructure
EstimateActivityDurations Activitydurationestimates
DevelopSchedule ProjectscheduleProjectbaseline
ControlSchedule WorkperformancemeasuresChangerequested
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• TimeManagementfocusesonhowandwhentheworkistobeaccomplished• Itisdifferentfromscopingwhichfocusedonwhatwastobeaccomplished
Es?mateAc?vityDura?ons
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Es?mateAc?vityDura?ons6.5EstimateActivityDurations� EstimateActivityDurationsistheprocessofestimatingthenumberofworkperiodsneededtocompleteindividualactivitieswithestimatedresources.� Estimatingactivitydurationsisconcernedwithdeterminingtheactualworkhoursneededtocompletethework(effort)andthenumberofworkdaysitwilltakefromstarttofinish(duration).
� Thekeybenefitofthisprocessisthatitprovidestheamountoftimeeachactivitywilltaketocomplete,whichisamajorinputintotheDevelopScheduleprocess.
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RefiningEs?mateAc?vityDura?ons� Forprojectsthathavestablerequirements,commontechnologyandateamthathasexperience,youwillprobablybeabletogetgoodestimatesearlyintheprocess,� Theywillmostlikelyberelativelyaccurateandwon’tneedalotofrefinement
� Conversely,projectsthatareusingnewtechnologyandhaveevolvingscopeandrequirementswillneedmanyiterationsofestimating� Estimatesforthistypeofprojectwillhaveawiderangeandtheyarelikelytochangeoverthelifeoftheproject
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Inputs,ToolsandOutputsForEs?mateAc?vityDura?ons
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PMBOKFigure6-14
166 ©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
Inputs Tools & Techniques Outputs
.1 Schedule management plan .2 Activity list .3 Activity attributes .4 Activity resource requirements .5 Resource calendars .6 Project scope statement .7 Risk register .8 Resource breakdown structure .9 Enterprise environmental factors.10 Organizational process assets
.1 Expert judgment
.2 Analogous estimating
.3 Parametric estimating
.4 Three-point estimating
.5 Group decision-making techniques.6 Reserve analysis
.1 Activity duration estimates.2 Project documents updates
Figure 6-14. Estimate Activity Durations: Inputs, Tools & Techniques, and Outputs
Project Time Management
6.5EstimateActivity
Durations
6.1Plan ScheduleManagement
6.2Define
Activities
6.4Estimate Activity
Resources
6.6DevelopSchedule
A
A
P
Activity
ProjectDocuments
O
12.2Conduct
Procurement
9.2Acquire
Project Team
11.2IdentifyRisks
5.3DefineScope
Enterprise/Organization
11.2IdentifyRisks
Figure 6-15. Estimate Activity Durations Data Flow Diagram
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
FlowDiagramForEs?mateAc?vityDura?ons
12PMBOKFigure6-15
166 ©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
Inputs Tools & Techniques Outputs
.1 Schedule management plan .2 Activity list .3 Activity attributes .4 Activity resource requirements .5 Resource calendars .6 Project scope statement .7 Risk register .8 Resource breakdown structure .9 Enterprise environmental factors.10 Organizational process assets
.1 Expert judgment
.2 Analogous estimating
.3 Parametric estimating
.4 Three-point estimating
.5 Group decision-making techniques.6 Reserve analysis
.1 Activity duration estimates.2 Project documents updates
Figure 6-14. Estimate Activity Durations: Inputs, Tools & Techniques, and Outputs
Project Time Management
6.5EstimateActivity
Durations
6.1Plan ScheduleManagement
6.2Define
Activities
6.4Estimate Activity
Resources
6.6DevelopSchedule
A
A
P
Activity
ProjectDocuments
O
12.2Conduct
Procurement
9.2Acquire
Project Team
11.2IdentifyRisks
5.3DefineScope
Enterprise/Organization
11.2IdentifyRisks
Figure 6-15. Estimate Activity Durations Data Flow Diagram
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
AFewNotesOnInputsForEs?mateAc?vityDura?ons� SomeoftheInputsderivefrompreviouslydescribedactivities
� ScheduleManagementPlan,ActivityListandAttributes,ActivityResourceRequirements,RBS,ResourceCalendar,EnvironmentalFactors,OrganizationalAssets,etc.
� ProjectScopeStatement� Theassumptionsandconstraintsfromtheprojectscopestatement
areconsideredwhenestimatingtheactivitydurations.� Examplesofassumptionsinclude:
� Existingconditions,� Availabilityofinformation� Lengthofthereportingperiods
� Examplesofconstraintsinclude:� Availableskilledresources� Contracttermsandrequirements.
� RiskRegister� Providesthelistofrisks,alongwiththeresultsofriskanalysisand
riskresponseplanningthatmayimpactactivityduration13
ProjectManagerRoleInEs?mateAc?vityDura?ons� TherolesofthePMinestimatinginclude:
� Providetheteamwithenoughinformationtoproperlyestimateeachactivity� Activitymustbeatalowenoughlevel
� Lettheestimatorsknowhowrefinedtheestimatesmustbe
� Completeasanitycheckoftheestimates� Preventpadding
� Paddingisjusttakingyourbestguessanddoublingit� Thisisdifferentfromcreatingamanagementreserveforrisk
� Formulateareserve� Makesurethatallassumptionsmadeduringestimation,aswellastheestimatesthemselves,arefullydocumented
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ToolsForEs?mateAc?vityDura?ons–ExpertJudgment� Expertjudgment,guidedbyhistoricalinformation,canprovidedurationestimateinformationorrecommendedmaximumactivitydurationsfrompriorsimilarprojects
� Expertjudgmentcanalsobeusedtodeterminewhethertocombinemethodsofestimatingandhowtoreconciledifferencesbetweenthem
� Whenperformingearlyestimatesforlargerprojects,thewholeteamwon’talwaysbeavailable� Projectleadersshouldhavetheexperiencetocontributetotheestimatingprocess
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ToolsForEs?mateAc?vityDura?ons–AnalogousEs?ma?ng(1)� Analogousestimatingisatechniqueforestimatingthedurationorcostofanactivityoraprojectusinghistoricaldatafromasimilaractivityorproject� Analogousestimatingusesparametersfromaprevious,similarproject,suchasduration,budget,size,weight,andcomplexity,asthebasisforestimatingthesameparameterormeasureforafutureproject
� Whenestimatingdurations,thistechniquereliesontheactualdurationofprevious,similarprojectsasthebasisforestimatingthedurationofthecurrentproject
� Itisagrossvalueestimatingapproach,sometimesadjustedforknowndifferencesinprojectcomplexity
� Analogousdurationestimatingisfrequentlyusedtoestimateprojectdurationwhenthereisalimitedamountofdetailedinformationabouttheproject
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ToolsForEs?mateAc?vityDura?ons–AnalogousEs?ma?ng(2)� Analogousestimatingisgenerallylesscostlyandlesstimeconsumingthanothertechniques,butitisalsolessaccurate� Analogousdurationestimatescanbeappliedtoatotalprojectortosegmentsofaprojectandmaybeusedinconjunctionwithotherestimatingmethods.
� Analogousestimatingismostreliablewhenthepreviousactivitiesaresimilarinfactandnotjustinappearance,andtheprojectteammemberspreparingtheestimateshavetheneededexpertise
� Examplesmayinclude:� Basinghowlongitwilltaketopavearoad,layapipe,etc.basedonsimilarprojects
� Estimatingthecostofinstallingnewsoftwarebasedonasimilarpreviousactivity
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ToolsForEs?mateAc?vityDura?ons–ParametricEs?ma?ng(1)� Parametricestimatingisanestimatingtechniqueinwhichan
algorithmisusedtocalculatecostordurationbasedonhistoricaldataandprojectparameters� Parametricestimatingusesastatisticalrelationshipbetweenhistorical
dataandothervariables(e.g.,squarefootageinconstruction)tocalculateanestimateforactivityparameters,suchascost,budget,andduration.
� Activitydurationscanbequantitativelydeterminedbymultiplyingthequantityofworktobeperformedbylaborhoursperunitofwork.� Forexample,activitydurationonadesignprojectisestimatedbythe
numberofdrawingsmultipliedbythenumberoflaborhoursperdrawing,oronacableinstallation,themetersofcablemultipliedbythenumberoflaborhourspermeter.� Iftheassignedresourceiscapableofinstalling25metersofcableperhour,the
durationrequiredtoinstall1,000metersis40hours.(1,000metersdividedby25metersperhour).
� Thistechniquecanproducehigherlevelsofaccuracydependinguponthesophisticationandunderlyingdatabuiltintothemodel.
� Parametrictimeestimatescanbeappliedtoatotalprojectortosegmentsofaproject,inconjunctionwithotherestimatingmethods.
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ToolsForEs?mateAc?vityDura?ons–ParametricEs?ma?ng(2)� Therearetwowaysthatanestimatormightcreateparametricestimates:� RegressionAnalysis(scatterdiagrams)
� Thisdiagramtrackstwovariablestoseeiftheyarerelatedandcreateamathematicalformulatouseinfutureestimates
� distance=speed*time(directrelationship)� density=mass/volume(inverserelationship)
� Learningcurve� The100THpaintedroomwilltakelesstimethanthefirst(inversehyperbolicrelationship)
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ToolsForEs?mateAc?vityDura?ons–One-PointEs?ma?ng� Inone-pointanalysistheestimatorsubmitsoneestimateperactivity� Estimatemaybebasedonhistoricaldata,expertjudgmentora
bestguess� One-pointanalysisisrarelyused,andmostbigcompanieshavepoliciesagainstit� Peopleusuallypadtheirestimates� Ithidesimportantinformationaboutriskanduncertaintyfromthe
projectmanager� Itoftenresultsinaschedulethatnoonebelievesin� Ifactualestimateisofftheestimator’sreputationmaybesullied� Estimatorsoftenworkagainsttheprojectmanagertotrytoprotect
themselves� Thistypeofestimationshouldnotbeusedonprojectsrequiringanythingbeyondatoplevelschedule� Ifitisbeingused,thePMmustprovidetheestimatorwithasmuch
dataaspossible,includingalltheinputstothisestimationactivity20
ToolsForEs?mateAc?vityDura?ons–Three-PointEs?ma?ng(1)� Theaccuracyofsingle-pointactivitydurationestimatesmaybeimprovedbyconsideringestimationuncertaintyandrisk� Statisticallythereisaverysmallprobabilityofcompletingaprojectexactlyonschedule
� Thisconceptoriginatedwiththeprogramevaluationandreviewtechnique(PERT)
� Thereforeitismuchbettertoprovidethreepointestimates� Estimatingwhatcangorightandwrongcanhelpestimatorsdetermineanexpectedrangeforeachactivity
� AssiststhePMinunderstandingtheprojectedvolatilityofanactivity
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ToolsForEs?mateAc?vityDura?ons–Three-PointEs?ma?ng(2)� PERTusesthreeestimatestodefineanapproximaterangeforanactivity’sduration:� Mostlikely(M)-Thisestimateisbasedonthedurationofthe
activity,giventheresourceslikelytobeassigned,theirproductivity,realisticexpectationsofavailabilityfortheactivity,dependenciesonotherparticipants,andinterruptions.
� Optimistic(O)-Theactivitydurationbasedonanalysisofthebest-casescenariofortheactivity
� Pessimistic(P)-Theactivitydurationbasedonanalysisoftheworst-casescenariofortheactivity
� Dependingontheassumeddistributionofvalueswithintherangeofthethreeestimatestheexpectedactivityduration,EAD,canbecalculatedusingaformula.ThemostcommonlyusedformulaisthebetadistributionfromthetraditionalPERTtechnique� EAD=(O+4M+P)/6
� Durationestimatesbasedonthreepointswithanassumeddistributionprovideanexpecteddurationandclarifytherangeofuncertaintyaroundtheexpectedduration
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ToolsForEs?mateAc?vityDura?ons–Three-PointEs?ma?ng(3)� Thestandarddeviationisanumericalvalueusedtoindicatehowwidelyestimatesvary� Itisthemeasureofdispersionofasetofdatafromitsmean.Itmeasurestheabsolutevariabilityofadistribution
� Thehigherthedispersionorvariability,thegreateristhestandarddeviationandgreaterwillbethemagnitudeofthedeviationofthevaluefromtheirmean.
� StandardDeviationisalsoknownasroot-meansquaredeviationasitisthesquarerootofmeansofthesquareddeviationsfromthearithmeticmean.
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ToolsForEs?mateAc?vityDura?ons–Three-PointEs?ma?ng(4)� Forourpurposesthestandarddeviationσisdefinedas:σ=(P-O)/6� Therangeofanestimateisthereforerunsfrom(EAD–σ)to(EAD+σ)� Wealsodefinevarianceasvar=σ2orvarianceisdefinedastheaverageofthesumofsquaresofthedifferencesfrommeanforasetofnumbersσ2 = Σ ( Xi – (Σ(Xi)/N) )2 / N Note: – (Σ(X)/N) is simply the average of the N numbers X1 … XN
� Typicallystandarddeviationisfoundbytakingthesquarerootofthevariance
� Thisisrequiredwhenyoubegintoanalyzeanentireprojectratherthanasingleactivity(seeexampletofollow
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ToolsForEs?mateAc?vityDura?ons–Three-PointEs?ma?ng(5)
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Activity P M O EAD STD Deviation
(σ)
Variance Range of The Estimate
A 47 27 14 28.167 5.500 30.250 22.667 to 33.667
B 89 60 41 61.667 8.000 64.000 53.667 to 69.667
C 48 44 39
D 42 37 29
Exercise:PleasefillthevaluesforactivitiesCandD
ToolsForEs?mateAc?vityDura?ons–Three-PointEs?ma?ng(6)
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Activity P M O EAD STD Deviation
(σ)
Variance Range of the Estimate
A 47 27 14 28.167 5.500 30.250 22.667 to 33.667
B 89 60 41 61.667 8.000 64.000 53.667 to 69.667
C 48 44 39 43.833 1.500 2.250 42.333 to 45.333
D 42 37 29 36.500 2.167 4.696 34.333 to 38.667
ToolsForEs?mateAc?vityDura?ons–Es?ma?ngTheProjectDura?on(1)
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Project Expected Project
Duration
Project STD
Deviation (σ)
Project Variance
Range of the Estimate
Project Duration Estimate
=sumofthedurations
=squarerootofthesumofthe
variances
=sumofthe
variances
=ExpectedDuration+/-the
StandardDeviation
Howlongshouldtheentireprojectwiththefouractivitiespreviouslydescribedtake?
ToolsForEs?mateAc?vityDura?ons–Es?ma?ngTheProjectDura?on(2)
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Project Expected Project
Duration
Project STD
Deviation (σ)
Project Variance
Range of the Estimate
Project Duration Estimate
170.167 10.060 101.196 160.107to180.227
Howlongshouldtheentireprojectwiththefouractivitiespreviouslydescribedtake?
ToolsForEs?mateAc?vityDura?ons–ReserveAnalysis(1)� Durationestimatesmayincludecontingencyreserves,sometimesreferredtoastimereservesorbuffers,intotheprojectscheduletoaccountforscheduleuncertainty� Contingencyreservesaretheestimateddurationwithintheschedulebaseline,whichisallocatedforidentifiedrisksthatareacceptedandforwhichcontingentormitigationresponsesaredeveloped
� Contingencyreservesareassociatedwiththe“known-unknowns,”whichmaybeestimatedtoaccountforthisunknownamountofrework
� Thecontingencyreservemaybeapercentageoftheestimatedactivityduration,afixednumberofworkperiods,ormaybedevelopedbyusingquantitativeanalysismethodssuchasMonteCarlosimulation
� Contingencyreservesmaybeseparatedfromtheindividualactivitiesandaggregatedintobuffers
� Contingencyreservesarenotpadding 29
ToolsForEs?mateAc?vityDura?ons–ReserveAnalysis(2)� Asmorepreciseinformationabouttheprojectbecomesavailable,thecontingencyreservemaybeused,reduced,oreliminated.� Contingencyshouldbeclearlyidentifiedinscheduledocumentation.
� Estimatesmayalsobeproducedfortheamountofmanagementreserveoftimefortheproject� Managementreservesareaspecifiedamountoftheprojectdurationwithheldformanagementcontrolpurposesandarereservedforunforeseenworkthatiswithinscopeoftheproject
� Managementreservesareintendedtoaddressthe“unknown-unknowns”thatcanaffectaproject
� Managementreserveisnotincludedintheschedulebaseline,butitispartoftheoverallprojectdurationrequirements
� Dependingoncontractterms,useofmanagementreservesmayrequireachangetotheschedulebaseline
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SpecialTopic–SoXwareEs?ma?onTechniques
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SoXwareEs?ma?ons-Introduc?on� Thegoalofsoftwareestimationistodeterminethedurationofasoftwareprojectsothatitcanbeproperlycosted
� Modelsexistthatareusedbyestimatorstoobtaintheprojecteddurationseachdeliverable,andtheprojectasawhole
� Themodelhelpsdefinelowerlevelactivities� Theseestimatesarethenfedintocostmodels� ForthistoworkestimatorsmustbeabletosizethesoftwareusingeithersoftwareLinesofCodeorFunctionPointanalysis� Theywillusethetechniquesofexpertexperience,analogousestimating,parametricestimating,three-pointestimatingetc.,todeveloptheseinputs
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SEERSEMEs?ma?ons(1)� SEERforSoftware(SEER-SEM)isanalgorithmicprojectmanagementsoftwareapplicationdesignedspecificallytoestimate,planandmonitortheeffortandresourcesrequiredforanytypeofsoftwaredevelopmentand/ormaintenanceproject.� SEER,whichcomesfromthenoun,referringtoonehavingtheabilitytoforeseethefuture
� Itreliesonparametricalgorithms,knowledgebases,simulation-basedprobability,andhistoricalprecedentstoallowprojectmanagers,engineers,andcostanalyststoaccuratelyestimateaproject'scostschedule,riskandeffortbeforetheprojectisstarted.
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SEERSEMEs?ma?ons(2)� SEERforSoftware(SEER-SEM)iscomposedofagroupofmodelsworkingtogethertoprovideestimatesofeffort,duration,staffing,anddefects.
� Thesemodelscanbebrieflydescribedbythequestionstheyask,whichbecomesthedialsthataresettofinetunethemodel:� Sizing-Howlargeisthesoftwareprojectbeingestimated(LinesofCode,FunctionPoints,UseCases,etc.)
� Technology-Whatisthepossibleproductivityofthedevelopers(capabilities,tools,practices,etc.)?
� EffortandScheduleCalculation-Whatamountofeffortandtimearerequiredtocompletetheproject?
� ConstrainedEffort/ScheduleCalculation-Howdoestheexpectedprojectoutcomechangewhenscheduleandstaffingconstraintsareapplied?
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SEERSEMEs?ma?ons(3)� ActivityandLaborAllocation– Howshouldactivitiesandlaborbeallocatedintotheestimate?
� CostCalculation-Givenexpectedeffort,duration,andthelaborallocation,howmuchwilltheprojectcost?
� DefectCalculation-Givenproducttype,projectduration,andotherinformation,whatistheexpected,objectivequalityofthedeliveredsoftware?� Rememberthatthereisacosttoquality
� MaintenanceEffortCalculation-Howmucheffortwillberequiredtoadequatelymaintainandupgradeafieldedsoftwaresystem?
� Progress-Howistheprojectprogressingandwherewillitendup.Alsohowtoreplan?
� Validity-Isthisdevelopmentachievablebasedonthetechnologyinvolved?
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SoXwareSizingTechniques(1)� Softwaresizeisakeyinputtoanyestimatingmodelandacrossmostsoftwareparametricmodels� Supportedsizingmetricsincludesourcelinesofcode(SLOC),
functionpoints,function-basedsizing(FBS)andarangeofothermeasures
� Theyaretranslatedforinternaluseintoeffectivesize(Se).isaformofcommoncurrencywithinthemodelandenablesnew,reused,andevencommercialoff-the-shelfcodetobemixedforanintegratedanalysisofthesoftwaredevelopmentprocess.
� ThegenericcalculationforSewhenestimatingsoftwarelinesofcode(SLOCs)is:
Se = NewCodeSize + ExistingCodeSize*(0.4*Redesign + 0.25 * Reimplementation + 0.35*Retest)
� Asindicated,Seincreasesindirectproportiontotheamountofnewsoftwarebeingdeveloped
� Seincreasesbyalesseramountaspreexistingcodeisreusedinaproject.Theextentofthisincreaseisgovernedbytheamountofrework(redesign,re-implementation,andretest)requiredtoreusethecode.
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SoXwareSizingTechniques(2)� WhileSLOCisanacceptedwayofmeasuringtheabsolutesizeofcodefromthe
developer'sperspective,metricssuchasfunctionpointscapturesoftwaresizefunctionallyfromtheuser'sperspective.
� Thefunction-basedsizing(FBS)metricextendsfunctionpointssothathiddenpartsofsoftwaresuchascomplexalgorithmscanbesizedmorereadily.� FBSistranslateddirectlyintounadjustedfunctionpoints(UFP),thatis,existingcodeis
notnecessarilytakenintoaccount.� InSEER-SEM,allsizemetricsaretranslatedtoSe,includingthoseenteredusing
FBS� Thisisnotasimpleconversion,i.e.,notalanguage-drivenadjustment� Rather,themodelincorporatesfactors,includingphaseatestimate,operating
environment,applicationtype,andapplicationcomplexity� AlltheseconsiderationssignificantlyaffectthemappingbetweenfunctionalsizeandSe
� AfterFBSistranslatedintofunctionpoints,itisthenconvertedintoSe Se = Lx * (AdjFactor * UFP) (Entropy/1.2) Lxisalanguage-dependentexpansionfactorAdjFactoristheoutcomeinvolvingthefactorsmentionedaboveEntropyrangesfrom1.04to1.2dependingonthetypeofsoftwarebeingdeveloped(embedded,critical,business,etc.)
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MeasuringEffortandDura?on(1)� Aproject'seffortanddurationareinterrelated,asisreflectedintheircalculation
withinthemodel.� Effort(K)drivesduration,notwithstandingproductivity-relatedfeedbackbetween
durationconstraintsandeffort.Thebasiceffortequationis:
K = D0.4 * (Se/Cte)E
� Se-Alreadydefinedforthedifferentmodels� Cteiseffectivetechnology-acompositemetricthatcapturesfactorsrelatingtothe
efficiencyorproductivitywithwhichdevelopmentcanbecarriedout.� Anextensivesetofpeople,process,andproductparametersfeedintotheeffective
technologyrating� Ahigherratingmeansthatdevelopmentwillbemoreproductive
� Disstaffingcomplexity-aratingoftheproject'sinherentdifficultyintermsoftherateatwhichstaffareaddedtoaproject.
� Eistheentropy� Originallyentropywasfixedat1.2� Nextitevolvedto1.04to1.2dependingonprojectattributeswithsmallerIToriented
projectstendingtowardthelower� Currentlyentropyisobservedas1.0to1.2dependingonprojectattribute� SEERwillallowanentropylessthan1.0ifsuchacircumstanceisobservedaswell
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MeasuringEffortandDura?on(2)� Onceeffortisobtained,durationissolvedusingthefollowingequation:
td = = D-0.2 * (Se/Cte)0.4 � Thedurationequationisderivedfromkeyformulaicrelationships� Itsexponentindicatesthatasaproject'ssizeincreases,durationalsoincreases,though
lessthanproportionally� Thissize-durationrelationshipisalsousedincomponent-levelschedulingalgorithms
withtaskoverlapscomputedtofallwithintotalestimatedprojectduration.
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DevelopSchedule
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DevelopSchedule6.6DevelopSchedule� DevelopScheduleistheprocessofanalyzingactivitysequences,durations,resourcerequirements,andscheduleconstraintstocreatetheprojectschedulemodel� Thekeybenefitofthisprocessisthatbyenteringscheduleactivities,durations,resources,resourceavailabilities,andlogicalrelationshipsintotheschedulingtool,itgeneratesaschedulemodelwithplanneddatesforcompletingprojectactivities
� Remember,thescheduleisapartoftheProjectPlan,itisnottheProjectPlan
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Inputs,ToolsandOutputsForDevelopSchedule
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PMBOKFigure6-16
173©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
Inputs Tools & Techniques Outputs
.1 Schedule management plan .2 Activity list .3 Activity attributes .4 Project schedule network diagrams .5 Activity resource requirements .6 Resource calendars .7 Activity duration estimates .8 Project scope statement .9 Risk register .10 Project staff assignments.11 Resource breakdown structure.12 Enterprise environmental factors.13 Organizational process assets
.1 Schedule network analysis.2 Critical path method.3 Critical chain method.4 Resource optimization techniques.5 Modeling techniques.6 Leads and lags.7 Schedule compression.8 Scheduling tool
.1 Schedule baseline
.2 Project schedule
.3 Schedule data
.4 Project calendars
.5 Project management plan updates.6 Project documents updates
Figure 6-16 Develop Schedule: Inputs, Tools & Techniques, and Outputs
Project Time Management
6.6DevelopSchedule
6.7Control
Schedule
A
A
A
P
P
Project
Projectt
ProjectDocuments
r
P
12.2Conduct
Procurements
9.2Acquire
Project Team
11.2IdentifyRisks
5.3DefineScope
Enterprise/Organization
7.3Determine
Budget
7.2Estimate
Costs
4.2Develop ProjectManagement
Plan
12.1Plan Procurement
Management
6.5Estimate Activity
Durations
6.4Estimate Activity
Resources
6.3SequenceActivities
6.2Define
Activities
e
6.1Plan ScheduleManagement
Figure 6-17. Develop Schedule Data Flow Diagram
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
FlowDiagramForDevelopSchedule
43PMBOKFigure6-17
173©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
Inputs Tools & Techniques Outputs
.1 Schedule management plan .2 Activity list .3 Activity attributes .4 Project schedule network diagrams .5 Activity resource requirements .6 Resource calendars .7 Activity duration estimates .8 Project scope statement .9 Risk register .10 Project staff assignments.11 Resource breakdown structure.12 Enterprise environmental factors.13 Organizational process assets
.1 Schedule network analysis.2 Critical path method.3 Critical chain method.4 Resource optimization techniques.5 Modeling techniques.6 Leads and lags.7 Schedule compression.8 Scheduling tool
.1 Schedule baseline
.2 Project schedule
.3 Schedule data
.4 Project calendars
.5 Project management plan updates.6 Project documents updates
Figure 6-16 Develop Schedule: Inputs, Tools & Techniques, and Outputs
Project Time Management
6.6DevelopSchedule
6.7Control
Schedule
A
A
A
P
P
Project
Projectt
ProjectDocuments
r
P
12.2Conduct
Procurements
9.2Acquire
Project Team
11.2IdentifyRisks
5.3DefineScope
Enterprise/Organization
7.3Determine
Budget
7.2Estimate
Costs
4.2Develop ProjectManagement
Plan
12.1Plan Procurement
Management
6.5Estimate Activity
Durations
6.4Estimate Activity
Resources
6.3SequenceActivities
6.2Define
Activities
e
6.1Plan ScheduleManagement
Figure 6-17. Develop Schedule Data Flow Diagram
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
RefiningProjectSchedules� Thescheduleisonlyasgoodastheinputsgeneratedforit� Theschedulemayberefinedasapartofrollingwaveplanningandprogressiveelaboration-itisoftenaniterativeprocess.� Theschedulemodelisusedtodeterminetheplannedstartand
finishdatesforprojectactivitiesandmilestonesbasedontheaccuracyoftheinputs
� Scheduledevelopmentcanrequirethereviewandrevisionofdurationestimatesandresourceestimatestocreatetheprojectschedulemodeltoestablishanapprovedprojectschedulethatcanserveasabaselinetotrackprogress
� Oncetheactivitystartandfinishdateshavebeendetermined,itiscommontohaveprojectstaffassignedtotheactivitiesreviewtheirassignedactivitiesandconfirmthatthestartandfinishdatespresentnoconflictwithresourcecalendarsorassignedactivitiesinotherprojectsortasksandthusarestillvalid
� Asworkprogresses,revisingandmaintainingtheprojectschedulemodeltosustainarealisticschedulecontinuesthroughoutthedurationoftheproject
� OnceascheduleisbaselineditcanonlybeupdatedthroughaformalChangeManagementprocess
44
Star?ngDevelopmentOfAProjectSchedule� Todevelopaprojectscheduleyouneedthefollowinginformation:� Anunderstandingoftheworkrequiredtodeveloptheprojectincludingassumptions,milestonesandconstraints
� Theactivitylist� Thenetworkdiagram� Anestimateofthedurationofeachactivity� Anestimateofrequiredresourcesforeachactivity� Anunderstandingoftheavailabilityofresources–theresourcecalendar
� Acompanycalendar
45
HowDoYouDevelopAProjectSchedule� Todevelopaprojectschedulethatisboughtinto,approvedrealisticandformalyouneedtodothefollowing� Workwithstakeholderpriorities� Lookforalternativewaystocompletethework� Understandimpactsonotherprojects� Negotiateforresources� Applyleadsandlagstotheschedulewhereappropriate� Compresstheschedulebycrashing,fast-trackingandreestimating
wherenecessary� AdjusttheProjectManagementPlanwherenecessary–i.e.adjust
theWBSbecauseofplannedriskresponses� Inputdataintoaschedulingtoolandperformcalculationsto
optimizetheschedule� SimulatetheprojectusingMonteCarloanalysistodeterminethe
likelihoodofcompletingtheprocessontime� Levelresourceswherenecessary� Utilizepeer/teamreviews� Obtainstakeholderbuy-inandmanagementapproval
46
ToolsForProjectManagement–ScheduleNetworkAnalysis� Schedulenetworkanalysisisatechniquethatgeneratestheprojectschedulemodel� Itemploysvariousanalyticaltechniques,suchascriticalpathmethod,criticalchainmethod,what-ifanalysis,andresourceoptimizationtechniquestocalculatetheearlyandlatestartandfinishdatesfortheuncompletedportionsofprojectactivities.
� Somenetworkpathsmayhavepointsofpathconvergenceorpathdivergencethatcanbeidentifiedandusedinschedulecompressionanalysisorotheranalyses
47
ToolsForProjectManagement–Cri?calPathMethod-Overview� ACriticalPathisacombinationofactivitiesthat,ifanyaredelayed,willdelaytheproject’sfinish
� TheCriticalPathMethod(CPM)isananalysistechniquewiththreemainpurposes� Calculatetheproject’sfinishdate� Identifyhowmuchindividualactivitiesintheschedulecanslip
withoutchangingtheprojectfinishdate� Identifytheactivitieswiththehighestriskthatcannotslipwithout
changingtheprojectfinishdate� TheCPMentailsdeterminingtherangeoftimeswithinwhichtheactivitiescanoccur� Thisisdonebydeterminingtheearlystartandfinishdatesfor
eachactivityandthelatestartandfinishdatesforeachactivity� Theserepresenttherangeofdatesthateachactivitycanstart.
� Nextsectiondescribesthedetailedtechniquesusedinthecriticalpathmethods,anddemonstratesthosetechniques
48
ToolsForProjectManagement–Cri?calChainMethod(1)� Thecriticalchainmethod(CCM)isaschedulemethodthatallowstheprojectteamtoplacebuffersonanyprojectschedulepathtoaccountforlimitedresourcesandprojectuncertainties� Itisdevelopedfromthecriticalpathmethodapproachandconsiderstheeffectsofresourceallocation,resourceoptimization,resourceleveling,andactivitydurationuncertaintyonthecriticalpathdeterminedusingthecriticalpathmethod.
� Todoso,thecriticalchainmethodintroducestheconceptofbuffersandbuffermanagement� Thecriticalchainmethodusesactivitieswithdurationsthatdonot
includesafetymargins,logicalrelationships,andresourceavailability
� Insteadstatisticallydeterminedbufferscomposedoftheaggregatedsafetymarginsofactivitiesatspecifiedpointsontheprojectschedulepathtoaccountforlimitedresourcesandprojectuncertainties
� Theresource-constrainedcriticalpathisknownasthecriticalchain
49
ToolsForProjectManagement–Cri?calChainMethod(2)� Thecriticalchainmethodaddsdurationbuffersthatarenon-workscheduleactivitiestomanageuncertainty� Onebuffer,placedattheendofthecriticalchain,asshowninthenextfigureisknownastheprojectbufferandprotectsthetargetfinishdatefromslippagealongthecriticalchain
� Additionalbuffers,knownasfeedingbuffers,areplacedateachpointwhereachainofdependentactivitiesthatarenotonthecriticalchainfeedsintothecriticalchain
� Feedingbuffersthusprotectthecriticalchainfromslippagealongthefeedingchains� Thesizeofeachbuffershouldaccountfortheuncertaintyinthe
durationofthechainofdependentactivitiesleadinguptothatbuffer
� Oncethebufferscheduleactivitiesaredetermined,theplannedactivitiesarescheduledtotheirlatestpossibleplannedstartandfinishdates
� Consequently,insteadofmanagingthetotalfloatofnetworkpaths,thecriticalchainmethodfocusesonmanagingtheremainingbufferdurationsagainsttheremainingdurationsofchainsofactivities 50
FlowDiagramForTheCri?calChainMethod
51PMBOKFigure6-19
178 ©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6.6.2.3 Critical Chain Method
The critical chain method (CCM) is a schedule method that allows the project team to place buffers on any project schedule path to account for limited resources and project uncertainties. It is developed from the critical path method approach and considers the effects of resource allocation, resource optimization, resource leveling, and activity duration uncertainty on the critical path determined using the critical path method. To do so, the critical chain method introduces the concept of buffers and buffer management. The critical chain method uses activities with durations that do not include safety margins, logical relationships, and resource availability with statistically determined buffers composed of the aggregated safety margins of activities at specified points on the project schedule path to account for limited resources and project uncertainties. The resource-constrained critical path is known as the critical chain.
The critical chain method adds duration buffers that are non-work schedule activities to manage uncertainty. One buffer, placed at the end of the critical chain, as shown in Figure 6-19, is known as the project buffer and protects the target finish date from slippage along the critical chain. Additional buffers, known as feeding buffers, are placed at each point where a chain of dependent activities that are not on the critical chain feeds into the critical chain. Feeding buffers thus protect the critical chain from slippage along the feeding chains. The size of each buffer should account for the uncertainty in the duration of the chain of dependent activities leading up to that buffer. Once the buffer schedule activities are determined, the planned activities are scheduled to their latest possible planned start and finish dates. Consequently, instead of managing the total float of network paths, the critical chain method focuses on managing the remaining buffer durations against the remaining durations of chains of activities.
Activity A
Critical Chain LinkNon-Critical Link
Activity CStart Finish
Activity G
Activity B
Activity D
FeedingBuffer
FeedingBuffer
Activity E Activity F ProjectBuffer
KEY
Figure 6-19. Example of Critical Chain Method
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
ToolsForProjectManagement–ResourceOp?miza?onTechniques(1)
� Thereareseveralmethodsthatcanbeusedtooptimizetheuseofresources
� ResourceLeveling� Atechniqueinwhichstartandfinishdatesareadjustedbasedonresourceconstraintswiththegoalofbalancingdemandforresourceswiththeavailablesupply
� Resourcelevelingcanbeusedwhensharedorcriticallyrequiredresourcesareonlyavailableatcertaintimes,orinlimitedquantities,orover-allocated,suchaswhenaresourcehasbeenassignedtotwoormoreactivitiesduringthesametimeperiod,asshowninthenextfigure,
� Alsousedtokeepresourceusageataconstantlevel� Resourcelevelingcanoftencausetheoriginalcriticalpathtochange,usuallytoincrease
52
ToolsForProjectManagement–ResourceOp?miza?onTechniques(2)
� ResourceSmoothing� Atechniquethatadjuststheactivitiesofaschedulemodelsuchthattherequirementsforresourcesontheprojectdonotexceedcertainpredefinedresourcelimits
� Inresourcesmoothing,asopposedtoresourceleveling,theproject’scriticalpathisnotchangedandthecompletiondatemaynotbedelayed
� Inotherwords,activitiesmayonlybedelayedwithintheirfreeandtotalfloat
� Thusresourcesmoothingmaynotbeabletooptimizeallresources.
53
ToolsForProjectManagement–ResourceOp?miza?onTechniques(3)–Example1
54PMBOKFigure6-20
179©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
6.6.2.4 Resource Optimization Techniques
Examples of resource optimization techniques that can be used to adjust the schedule model due to demand and supply of resources include, but are not limited to:
Resource leveling. A technique in which start and finish dates are adjusted based on resource constraints with the goal of balancing demand for resources with the available supply. Resource leveling can be used when shared or critically required resources are only available at certain times, or in limited quantities, or over-allocated, such as when a resource has been assigned to two or more activities during the same time period, as shown in Figure 6-20, or to keep resource usage at a constant level. Resource leveling can often cause the original critical path to change, usually to increase.
Start
Activity A Tom: 8 hrsSue: 8 hrs
Activity B Sue: 8 hrs
Activity C Tom: 8 hrs
Tom: 8 hrsSue: 16 hrs
Tom: 8 hrs
Day 2 Day 3Day 1
Start
Activity A Tom: 8 hrsSue: 8 hrs
Activity B Sue: 8 hrs
Activity C Tom: 8 hrs
Tom: 8 hrsSue: 8 hrs
Sue: 8 hrs Tom: 8 hrs
Day 2 Day 3Day 1
Activities Before Resource Leveling
Activities After Resource Leveling
Figure 6-20. Resource Leveling
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
ToolsForProjectManagement–ResourceOp?miza?onTechniques(3)–Example2
55
Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
InitialResourceUtilization
ToolsForProjectManagement–ResourceOp?miza?onTechniques(4)–Example2
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Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
ResourcesLeveledOverTime
ToolsForProjectManagement–ResourceOp?miza?onTechniques(5)–Example2
57
Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
WorkLeveledAcrossResources–Week1
ToolsForProjectManagement–ModelingTechniques(1)� Thereareseveralmethodsthatcanbeusedtomodelaschedule
� What-IfScenarioAnalysis� What-ifscenarioanalysisistheprocessofevaluatingscenariosinordertopredicttheireffect,positivelyornegatively,onprojectobjectives
� Thisisananalysisofthequestion,“Whatifthesituationrepresentedbyscenario‘X’happens?”
� Aschedulenetworkanalysisisperformedusingthescheduletocomputethedifferentscenarios,suchas:� Delayingamajorcomponentdelivery� Extendingspecificengineeringdurations� Introducingexternalfactors,suchasastrikeorachangeinthe
permittingprocess� Theoutcomeofthewhat-ifscenarioanalysiscanbeusedtoassessthefeasibilityoftheprojectscheduleunderadverseconditions,andinpreparingcontingencyandresponseplanstoovercomeormitigatetheimpactofunexpectedsituations
58
ToolsForProjectManagement–ModelingTechniques(2)
� Simulation� Simulationinvolvescalculatingmultipleprojectdurationswithdifferentsetsofactivityassumptions,usuallyusingprobabilitydistributionsconstructedfromthethree-pointestimatestoaccountforuncertainty
� ThemostcommonsimulationtechniqueisMonteCarloanalysisinwhichadistributionofpossibleactivitydurationsisdefinedforeachactivityandusedtocalculateadistributionofpossibleoutcomesforthetotalproject.
59
ToolsForProjectManagement–ModelingTechniques(3)
60PMBOKFigure11-17
340 ©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
11 - PROJECT RISK MANAGEMENT
Modeling and simulation. A project simulation uses a model that translates the specified detailed uncertainties of the project into their potential impact on project objectives. Simulations are typically performed using the Monte Carlo technique. In a simulation, the project model is computed many times (iterated), with the input values (e.g., cost estimates or activity durations) chosen at random for each iteration from the probability distributions of these variables. A histogram (e.g., total cost or completion date) is calculated from the iterations. For a cost risk analysis, a simulation uses cost estimates. For a schedule risk analysis, the schedule network diagram and duration estimates are used. The output from a cost risk simulation using the three-element model and risk ranges is shown in Figure 11-17. It illustrates the respective probability of achieving specific cost targets. Similar curves can be developed for other project objectives.
This cumulative distribution, assuming the data ranges in Figure 11-13 and triangular distributions, shows that the project is only 12 percent likely to meet the $41 million most likely cost estimate. If a conservative organization wants a 75% likelihood of success, a budget of $50 million (a contingency of nearly 22 % ($50M - $41M)/$41M)) is required.
Total Project CostCumulative Chart
Cost
100%
75%
50%
25%
0%
Prob
abili
ty
$30.00M $38.75M $47.50M $56.25M $65.00M
12%
Mean = $46.67M
$41M $50M
Figure 11-17. Cost Risk Simulation Results
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
ToolsForProjectManagement–LeadsandLags� LeadsandLags
� Whenappliedduringschedulingthesearerefinementsappliedduringnetworkanalysistodevelopaviableschedulebyadjustingthestarttimeofthesuccessoractivities
� Leadsareusedinlimitedcircumstancestoadvanceasuccessoractivitywithrespecttothepredecessoractivity
� Lagsareusedinlimitedcircumstanceswhereprocessesrequireasetperiodoftimetoelapsebetweenthepredecessorsandsuccessorswithoutworkorresourceimpact
61
ToolsForProjectManagement–ScheduleCompression(1)� Schedulecompressiontechniquesareusedtoshortenthescheduledurationwithoutreducingtheprojectscope,inordertomeetscheduleconstraints,imposeddates,orotherscheduleobjectives
� Schedulecompressiontechniquesinclude,butarenotlimitedtocrashingandfasttracking
� Crashing� Atechniqueusedtoshortenthescheduledurationfortheleast
incrementalcostbyaddingresources� Examplesofcrashinginclude
� Approvingovertime� Bringinginadditionalresources� Payingtoexpeditedeliverytoactivitiesonthecriticalpath
� Crashingworksonlyforactivitiesonthecriticalpathwhereadditionalresourceswillshortentheactivity’sduration
� Crashingdoesnotalwaysproduceaviablealternativeandmayresultinincreasedriskand/orcost� Ifonepersoncantaketendaystowriteaunititdoesn’tmeanthatten
peoplecandoitinoneday62
ToolsForProjectManagement–ScheduleCompression(2)
� FastTracking� Aschedulecompressiontechniqueinwhichactivitiesorphasesnormallydoneinsequenceareperformedinparallelforatleastaportionoftheirduration
� Anexampleisconstructingthefoundationforabuildingbeforecompletingallofthearchitecturaldrawings
� Fasttrackingmayresultinreworkandincreasedrisk� Fasttrackingonlyworksifactivitiescanbeoverlappedtoshortentheprojectduration
63
ToolsForProjectManagement–ScheduleCompression(3)
64
CompleteDrywall
PaintExterior
InstallCarpet
CompleteDrywall
PaintExterior
InstallCarpet
15Days
15Days
8Days 8Days
9Days
10Days
OriginalDuration31Days
FastTrackedDuration31Days
ToolsForProjectManagement–SchedulingTools� Automatedschedulingtoolscontaintheschedulemodelandexpeditetheschedulingprocessbygeneratingstartandfinishdatesbasedontheinputsof� Activities� Networkdiagrams� Resourcesandactivitydurationsusingschedulenetworkanalysis
� Aschedulingtoolcanbeusedinconjunctionwithotherprojectmanagementsoftwareapplicationsaswellasmanualmethods
� Examplesofschedulingtoolsinclude� MicrosoftProject� FastTrackSchedule9� PrimaveraP6–usedonlargeprojects� Workfront� GanttProject–freebutnotforbeginners� Bittrix24–alsofree 65
OutputsForProjectManagement–ScheduleBaseline� Aschedulebaselineistheapprovedversionofaschedulemodelthatcanbechangedonlythroughformalchangecontrolproceduresandisusedasabasisforcomparisontoactualresults
� Itisacceptedandapprovedbytheappropriatestakeholdersastheschedulebaselinewithbaselinestartdatesandbaselinefinishdates
� Duringmonitoringandcontrolling,theapprovedbaselinedatesarecomparedtotheactualstartandfinishdatestodeterminewhethervarianceshaveoccurred
� Theschedulebaselineisacomponentoftheprojectmanagementplan
66
OutputsForProjectManagement–ProjectSchedule(1)� Theoutputsfromaschedulemodelareschedulepresentations� Theprojectscheduleisanoutputofaschedulemodelthatpresentslinkedactivitieswithplanneddates,durations,milestones,andresources� Ataminimum,theprojectscheduleincludesaplannedordefined
startdateandplannedfinishdateforeachactivity� Ifresourceplanningisdoneatanearlystage,thentheprojectscheduleremainspreliminaryuntilresourceassignmentshavebeenconfirmedandscheduledstartandfinishdatesareestablished.� Thisprocessusuallyoccursnolaterthanthecompletionofthe
ProjectManagementPlan� Theprojectschedulepresentationmaybepresentedinsummary
form,sometimesreferredtoasthemasterscheduleormilestoneschedule,orpresentedindetail.
� Althoughaprojectschedulemodelcanbepresentedintabularform,itismoreoftenpresentedgraphically,usingoneormoreofthefollowingformatsdescribedinthenextfewpages
67
OutputsForProjectManagement–ProjectSchedule(2)� GanttCharts,alsoknowasBarCharts
� Ganttchartsrepresentscheduleinformationwhereactivitiesarelistedontheverticalaxis,datesareshownonthehorizontalaxis,andactivitydurationsareshownashorizontalbarsplacedaccordingtostartandfinishdates
� Barchartsarerelativelyeasytoread,andarefrequentlyusedinmanagementpresentations
� Forcontrolandmanagementcommunications,thebroader,morecomprehensivesummaryactivity,sometimesreferredtoasahammockactivity,isusedbetweenmilestonesoracrossmultipleinterdependentworkpackages,andisdisplayedinbarchartreports
68
OutputsForProjectManagement–ProjectSchedule(3)
69
SampleSummarySchedulePresentedInWBSFormat
183©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1.MB Begin New Product Z
Period 4Calendar
units
Calendarunits
Calendarunits
Complete Component 1
Complete Component 2
Finish New Product Z
0
0
0
0
Activity Description
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1.MB 0
120
67
20
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14
0
53
14
28
11
0
53
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Period 4Activity Description
1.1.1.M1
1.1.2.M1
1.1.3.MF
Complete Integration of Components 1 & 2 01.1.3.M1
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1 Develop and Deliver New Product Z
Period 4
Work Package 1: Component 1
Work Package 2: Component 2
Work Package 3: Integrated Components 1 and 2
120
67
53
53
Activity Description
1.1.1
1.1.2
1.1.3
Milestone Schedule
Data Date
Data DateDetailed Schedule
1.1.1.T
1.1
1.1.1
1.1.1.D
1.1.1.B
1.1.2.T
1.1.1.M1
1.1.2
1.1.2.D
1.1.2.B
1.1.3.M1
1.1.2.M1
1.1.3
1.1.3.G
1.1.3.T
Data Date
SS
FS
1.1.3.P
1.1.3.MF
Summary Schedule
Begin New Product Z
Develop and Deliver Product Z
Work Package 1: Component 1
Design Component 1
Build Component 1
Test Component 1
Complete Component 1
Work Package 2: Component 2
Design Component 2
Build Component 2
Test Component 2
Complete Component 2
Work Package 3: Integrated Components 1 and 2
Integrate Components 1 and 2 as Product Z
Complete Integration of Components 1 and 2
Test Integrated Components as Product Z
Deliver Product Z
Finish New Product Z
Figure 6-21. Project Schedule Presentations —Examples
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
PMBOKFigure6-21
OutputsForProjectManagement–ProjectSchedule(4)� Milestonecharts
� Thesechartsaresimilartobarcharts,butonlyidentifythescheduledstartorcompletionofmajordeliverablesandkeyexternalinterfaces.
70
OutputsForProjectManagement–ProjectSchedule(5)
71
183©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1.MB Begin New Product Z
Period 4Calendar
units
Calendarunits
Calendarunits
Complete Component 1
Complete Component 2
Finish New Product Z
0
0
0
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Activity Description
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1.MB 0
120
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Period 4Activity Description
1.1.1.M1
1.1.2.M1
1.1.3.MF
Complete Integration of Components 1 & 2 01.1.3.M1
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1 Develop and Deliver New Product Z
Period 4
Work Package 1: Component 1
Work Package 2: Component 2
Work Package 3: Integrated Components 1 and 2
120
67
53
53
Activity Description
1.1.1
1.1.2
1.1.3
Milestone Schedule
Data Date
Data DateDetailed Schedule
1.1.1.T
1.1
1.1.1
1.1.1.D
1.1.1.B
1.1.2.T
1.1.1.M1
1.1.2
1.1.2.D
1.1.2.B
1.1.3.M1
1.1.2.M1
1.1.3
1.1.3.G
1.1.3.T
Data Date
SS
FS
1.1.3.P
1.1.3.MF
Summary Schedule
Begin New Product Z
Develop and Deliver Product Z
Work Package 1: Component 1
Design Component 1
Build Component 1
Test Component 1
Complete Component 1
Work Package 2: Component 2
Design Component 2
Build Component 2
Test Component 2
Complete Component 2
Work Package 3: Integrated Components 1 and 2
Integrate Components 1 and 2 as Product Z
Complete Integration of Components 1 and 2
Test Integrated Components as Product Z
Deliver Product Z
Finish New Product Z
Figure 6-21. Project Schedule Presentations —Examples
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
SampleMilestoneChartPMBOKFigure6-21
OutputsForProjectManagement–ProjectSchedule(6)� ProjectScheduleNetworkDiagrams
� Thesediagramsarecommonlypresentedintheactivity-on-nodediagramformatshowingactivitiesandrelationshipswithoutatimescale,sometimesreferredtoasapurelogicdiagram,aswehavepreviouslydiscussed
� Alsopresentedinatime-scaledschedulenetworkdiagramformatthatissometimescalledalogicbarchart,asshownforthedetailedscheduleinthenextfigure� Thesediagrams,withactivitydateinformation,usuallyshowboth
theprojectnetworklogicandtheproject’scriticalpathscheduleactivities
� Thisexamplealsoshowshoweachworkpackageisplannedasaseriesofrelatedactivities
� Anotherpresentationoftheprojectschedulenetworkdiagramisatime-scaledlogicdiagram� Thesediagramsincludeatimescaleandbarsthatrepresentthe
durationofactivitieswiththelogicalrelationships� Itisoptimizedtoshowtherelationshipsbetweenactivitieswhere
anynumberofactivitiesmayappearonthesamelineofthediagraminsequence 72
OutputsForProjectManagement–ProjectSchedule(7)
73
SampleProjectScheduleNetworkChart
183©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1.MB Begin New Product Z
Period 4Calendar
units
Calendarunits
Calendarunits
Complete Component 1
Complete Component 2
Finish New Product Z
0
0
0
0
Activity Description
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1.MB 0
120
67
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Period 4Activity Description
1.1.1.M1
1.1.2.M1
1.1.3.MF
Complete Integration of Components 1 & 2 01.1.3.M1
Project Schedule Time Frame
Period 5Period 1 Period 2 Period 3Activity
Identifier
1.1 Develop and Deliver New Product Z
Period 4
Work Package 1: Component 1
Work Package 2: Component 2
Work Package 3: Integrated Components 1 and 2
120
67
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53
Activity Description
1.1.1
1.1.2
1.1.3
Milestone Schedule
Data Date
Data DateDetailed Schedule
1.1.1.T
1.1
1.1.1
1.1.1.D
1.1.1.B
1.1.2.T
1.1.1.M1
1.1.2
1.1.2.D
1.1.2.B
1.1.3.M1
1.1.2.M1
1.1.3
1.1.3.G
1.1.3.T
Data Date
SS
FS
1.1.3.P
1.1.3.MF
Summary Schedule
Begin New Product Z
Develop and Deliver Product Z
Work Package 1: Component 1
Design Component 1
Build Component 1
Test Component 1
Complete Component 1
Work Package 2: Component 2
Design Component 2
Build Component 2
Test Component 2
Complete Component 2
Work Package 3: Integrated Components 1 and 2
Integrate Components 1 and 2 as Product Z
Complete Integration of Components 1 and 2
Test Integrated Components as Product Z
Deliver Product Z
Finish New Product Z
Figure 6-21. Project Schedule Presentations —Examples
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.
PMBOKFigure6-21
OutputsForProjectManagement–ScheduleData� Thescheduledatafortheprojectschedulemodelisthecollectionofinformationfordescribingandcontrollingthescheduleincludingatleast� Schedulemilestones� Scheduleactivities� Activityattributes� Documentationofallidentifiedassumptionsandconstraints
� Theamountofadditionaldatavariesbyapplicationarea.Informationfrequentlysuppliedassupportingdetailincludes,butisnotlimitedto:� Resourcerequirementsbytimeperiod,oftenintheformofa
resourcehistogram� Alternativeschedules,suchasbest-caseorworst-case,not
resource-leveled,orresource-leveled,withorwithoutimposeddates
� Schedulingofcontingencyreserves� Scheduledatacouldalsoincludesuchitemsasresourcehistograms,cash-flowprojections,andorderanddeliveryschedules
74
OutputsForProjectManagement–ProjectCalendarsandProjectUpdates� TheProjectCalendaridentifiesworkingdaysandshiftsthatareavailableforscheduledactivities� Itdistinguishestimeperiodsindaysorpartsofdaysthatareavailabletocompletescheduledactivitiesfromtimeperiodsthatarenotavailable
� Aschedulemodelmayrequiremorethanoneprojectcalendartoallowfordifferentworkperiodsforsomeactivitiestocalculatetheprojectschedule
� Updatesmayoccurtoanyofthefollowingasaresultofprojectscheduling� ProjectManagementPlan� ActivityResourceRequirements� Activityattributes� Calendars� RiskRegister 75
DevelopScheduleADetailedLookAttheCri?calPathMethod
76
ToolsForProjectManagement–Cri?calPathMethod(1)� Thecriticalpathmethod(CPM)isamethodusedtoestimatetheminimumprojectdurationanddeterminetheamountofschedulingflexibilityonthelogicalnetworkpathswithintheschedulemodel� Thisschedulenetworkanalysistechniquecalculatestheearlystart,
earlyfinish,latestart,andlatefinishdatesforallactivitieswithoutregardforanyresourcelimitationsbyperformingaforwardandbackwardpassanalysisthroughtheschedulenetwork
� Thecriticalpathisthesequenceofactivitiesthatrepresentsthelongestpaththroughaproject,whichdeterminestheshortestpossibleprojectduration
� Theresultingearlyandlatestartandfinishdatesarenotnecessarilytheprojectschedule,rathertheyindicatethetimeperiodswithinwhichtheactivitycouldbeexecuted,usingtheparametersenteredintheschedulemodelforactivitydurations,logicalrelationships,leads,lags,andotherknownconstraints.
� Thecriticalpathmethodisusedtocalculatetheamountofschedulingflexibilityonthelogicalnetworkpathswithintheschedulemodel
77
ToolsForProjectManagement–Cri?calPathMethod(2)
� Onanynetworkpath,thescheduleflexibilityismeasuredbytheamountoftimethatascheduleactivitycanbedelayedorextendedfromitsearlystartdatewithoutdelayingtheprojectfinishdateorviolatingascheduleconstraint,andistermed“totalfloat.”
� ACPMcriticalpathisnormallycharacterizedbyzerototalfloatonthecriticalpath.� However,asimplementedwithPrecedenceDiagramModeling(PDM)
sequencing,criticalpathsmayhavepositive,zero,ornegativetotalfloatdependingonconstraintsapplied
� Anyactivityonthecriticalpathiscalledacriticalpathactivity.� Positivetotalfloatiscausedwhenthebackwardpassiscalculatedfroma
scheduleconstraintthatislaterthantheearlyfinishdatethathasbeencalculatedduringforwardpasscalculation.
� Negativetotalfloatiscausedwhenaconstraintonthelatedatesisviolatedbydurationandlogic.
� Schedulenetworksmayhavemultiplenear-criticalpaths.� Adjustmentstoactivitydurations(ifmoreresourcesorlessscopecanbe
arranged),logicalrelationships(iftherelationshipswerediscretionarytobeginwith),leadsandlags,orotherscheduleconstraintsmaybenecessarytoproducenetworkpathswithazeroorpositivetotalfloat.
� Oncethetotalfloatforanetworkpathhasbeencalculated,thenthefreefloat—theamountoftimethatascheduleactivitycanbedelayedwithoutdelayingtheearlystartdateofanysuccessororviolatingascheduleconstraint—canalsobedetermined.
78
ToolsForProjectManagement–Cri?calPathMethod–BasicDefini?ons(1)� EarlyStartDate(ES)
� IntheCPM,theearliestpossiblepointintimewhentheuncompletedportionsofascheduleactivitycanstartbasedontheschedulenetworklogicandanyscheduleconstraints
� EarlyFinishdate(EF)� IntheCPM,theearliestpossiblepointintimewhenthe
uncompletedportionsofascheduleactivity(ortheproject)canfinishbasedontheschedulenetworklogicandanyscheduleconstraints
� LateStartDate(LS)� IntheCPM,thelatestpossiblepointintimewhenthe
uncompletedportionsofascheduleactivitycanstartbasedupontheschedulenetworklogic,theprojectcompletiondate,andanyscheduleconstraints
� LateFinishDate(LF)� IntheCPM,thelatestpossiblepointintimewhenthe
uncompletedportionsofascheduleactivitycanfinishbasedontheschedulenetworklogic,theprojectcompletiondate,andanyscheduleconstraints
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ToolsForProjectManagement–Cri?calPathMethod–BasicDefini?ons(2)� TotalFloat
� Thetotalamountoftimethatascheduleactivitymaybedelayedorextendedfromitsearlystartdatewithoutdelayingtheprojectfinishdate,orviolatingascheduleconstraint(suchasamandatorymilestonedate)
� Thisissimplythemathematicaldifferencebetweentheearlyandlatestart(orfinish)dates� TotalFloat=LS-ESorTotalFloat=LF-EF
� Anactivitywithfloathassomeschedulingflexibility� Onceyouknowthecriticalandnearcriticalpathsyoucanusefloatasanassettoachieveabetterallocationofresources
� However,keepinmindthatthefutureactivitiesmaybeaffectedbyshiftingthestartorfinishdatewithinthefloat
� Youwillhavetounderstandtheimplicationstootheractivitiesthatsharethepathtoensureyouarenotcreatingresourceissues
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ToolsForProjectManagement–Cri?calPathMethod–BasicDefini?ons(3)� Thoseactivitieswithnofloatareonthecriticalpath.
� Thecriticalpathusuallyhaszerofloat,butitcanalsobeinterpretedasthatpathwiththeleastamountoffloat
� Thatmeansthattherecanbenegativefloat� Negativefloatoccurswhenanactivity’sstartdatacomesbeforetheprecedingactivity’sfinishdate–obviouslyaproblem
� Thecementismixedbeforetheholetopouritinhasbeencompleted
� Inthissituation,youmustfindawaytocompresstheschedule,ortheproject
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ToolsForProjectManagement–Cri?calPathMethod–BasicDefini?ons(4)� FreeFloat
� Theamountoftimethatascheduleactivitycanbedelayedwithoutdelayingtheearlystartdateofanysuccessororviolatingascheduleconstraint
� Freefloatisthemathematicaldifferencebetweentheearlyfinishofapredecessortask,andtheearlystartofthesuccessortask� Thishappenswhentherearemultiplepathsconvergingintoone
� Thelastactivitybeforeconvergingonthepath(s)thatarenotcriticalhavefreefloat
� Activitieswithfreefloathavethemostflexibilitybecauseiftheystartwithinthefreefloattime,thereshouldbenoscheduleimplicationsforanyotheractivitiesintheschedule
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TheCri?calPathMethod–Example1(1)
83
A
2
B
1
C
4
D
6
E
3
F
3
Start Finish
Path Activities Duration
Start-A-B-C-Finish 2+1+4 7
Start-D-C-Finish 6+4 10
Start-D-E-F-Finish 6+3+3 12 (Critical Path)
TheCri?calPathMethod–Example1(2)–ForwardPass
84
A
2
B
1
C
4
D
6
E
3
F
3
Start Finish
0 2 2 3 6 10
0 6 6 9 9 12
• TocalculatetheES/EFyouusetheforwardpass• BeginatStart=0andcalculatetheESbasedontheEFofthe
predecessor• NotethefreefloatbetweenBandCis3
TheCri?calPathMethod–Example1(3)–BackwardPass
85
• TocalculatetheLS/LFyouusethebackwardpass• BeginatEnd=EFandcalculatetheLFbasedontheLSofthe
successor• NodifferencebetweenES/LSandEF/LFpairsonthecritical
path• Thereisnofloatfortasksonthecriticalpath
A
2
B
1
C
4
D
6
E
3
F
3
Start Finish
0 2 2 3 6 10
0 6 6 9 9 12
9 12
8 12
6 9 0 6
7 8 5 7
TheCri?calPathMethod–Example2(1)–NetworkWithDura?ons
86
Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
TheCri?calPathMethod–Example2(2)–ForwardPass
87
Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
TheCri?calPathMethod–Example2(3)–BackwardPass
88
Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
TheCri?calPathMethod–Example2(4)–WithCalculatedFloat
89
Snyder, Cynthia Stackpole. A User's Manual to the PMBOK Guide (2). Somerset, US: John Wiley & Sons, Incorporated, 2013. ProQuest ebrary. Web. 1 May 2017.Copyright © 2013. John Wiley & Sons, Incorporated. All rights reserved.
• Total Float = LS-ES or Total Float = LF-EF • Free float is the mathematical difference between
the early finish of a predecessor task, and the early start of the successor task
TheCri?calPathMethod-AlternateFormat
90PMBOKFigure6-18
177©2013 Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Fifth Edition
6 - PROJECT TIME MANAGEMENT
6
On any network path, the schedule flexibility is measured by the amount of time that a schedule activity can be delayed or extended from its early start date without delaying the project finish date or violating a schedule constraint, and is termed “total float.” A CPM critical path is normally characterized by zero total float on the critical path. As implemented with PDM sequencing, critical paths may have positive, zero, or negative total float depending on constraints applied. Any activity on the critical path is called a critical path activity. Positive total float is caused when the backward pass is calculated from a schedule constraint that is later than the early finish date that has been calculated during forward pass calculation. Negative total float is caused when a constraint on the late dates is violated by duration and logic. Schedule networks may have multiple near-critical paths. Many software packages allow the user to define the parameters used to determine the critical path(s). Adjustments to activity durations (if more resources or less scope can be arranged), logical relationships (if the relationships were discretionary to begin with), leads and lags, or other schedule constraints may be necessary to produce network paths with a zero or positive total float. Once the total float for a network path has been calculated, then the free float—the amount of time that a schedule activity can be delayed without delaying the early start date of any successor or violating a schedule constraint—can also be determined. For example the free float for Activity B, in Figure 6-18, is 5 days.
Critical Path LinkNon-Critical Path Link
ActivityNode
Start FinishA
1 5 5
1 0 5
C
6 10 15
6 0 15
B
6 5 10
11 5 15
D
16 15 30
16 0 30
Activity Name
EarlyStart Duration
EarlyFinish
LateStart
TotalFloat
LateFinish
Path A–B–D = 25
Path A–C–D = 30(Critical Path)
KEY
Figure 6-18. Example of Critical Path Method
Licensed To: Howard Rosenthal PMI MemberID: 2552551This copy is a PMI Member benefit, not for distribution, sale, or reproduction.