The Practice of                                    Software Estimation  © 2008 by Phymata Solutions Inc. (Everett Toews)  ...
Presentation Roadmap©  Overview   2008 by PhymataSolutions Inc.   Techniques(Everett Toews)This presentation may   Pres...
Why Talk About Software            Estimation?©  My Motivation   2008 by PhymataSolutions Inc.   Advancing the Art and S...
Current State of Software               Estimation©  Most companies looking to avoid   2008 by PhymataSolutions Inc.     ...
Estimates, Targets and             Commitments©  Estimate (layman’s definition) – A prediction of   2008 by Phymata     h...
What is a Good Estimate?    Single point estimates are meaningless© 2008 by PhymataSolutions Inc.(Everett Toews)This pres...
What is a Good Estimate?©  Making a commitment   2008 by PhymataSolutions Inc.   Ability to support a project’s success(...
How Good an Estimator Are You?  1.   Surface temperature of the Sun© 2. Latitude of Shanghai   2008 by PhymataSolutions In...
How Good an Estimator Are You?  1.   10,0000F / 6,0000C© 2. 31 Phymata North  2008 by Degrees       17,139,000 miles2 / 44...
90% Confident©  90% confident closer to 30% confident   2008 by PhymataSolutions Inc.(Everett Toews) ranges are more accu...
Overestimate or Underestimate©  Arguments against overestimation   2008 by PhymataSolutions Inc.   Arguments again under...
Benefits of Accurate Estimates©  Improved status visibility   2008 by PhymataSolutions Inc.   Higher quality(Everett Toe...
The Cone of Uncertainty© 2008 by PhymataSolutions Inc.(Everett Toews)This presentation maynot be modified inany way.Permis...
Where Does Estimation               Error Come From?    Chaotic development process©2008 by PhymataSolutions Inc. requir...
Estimate Influences©  Size   2008 by PhymataSolutions Inc.   Diseconomies of scale(Everett Toews)This presentation mayno...
Estimate Influences© 1. Product complexity   2008 by PhymataSolutions Inc.  2. Requirements analyst capability(Everett Toe...
Considerations in Choosing        Estimation Techniques©  What’s being estimated?   2008 by PhymataSolutions Inc.(Everett...
Count, Compute, Judge            Count            Com put e©What by Phymata   2008     Size, Features   Size, Effort, Sche...
What to Count©  Something that is highly correlated   2008 by PhymataSolutions Inc.   Something available sooner than la...
Calibration and Historical Data            Calibrat e w it h       Calibrat ion w it h     Calibrat ion w it h© 2008 byI n...
Historical Data©  Accounts for organizational influences   2008 by PhymataSolutions Inc.(Everett Toews)subjectivity, unfo...
Individual Expert Judgment         Use of St ruct ured   Use of Est imat ion   Est imat ing Task         Comparing Task© 2...
Use of Ranges©  Single point estimates are bad   2008 by PhymataSolutions Inc.   Best case/Worst case(Everett Toews)This...
Compare Estimates to Actuals©  Magnitude of Relative Error =   2008 by PhymataSolutions Inc.     (ActualResult - Estimate...
Decomposition and Recomposition                        Decom posit ion by   Com put ing Best and© 2008 byDecom posit ion b...
Estimation by Analogy            Est imat ion by Analogy©What by Phymata Schedule, Features   2008     Size, Effort,Soluti...
Estimation by Analogy© 1. Similar previous project   2008 by PhymataSolutions Inc.  2. Compare(Everett Toews)This presenta...
Proxy-Based Estimates                           St andard© 2008FuzzyPhymata          by Logic         Component s         ...
Proxy-Based Estimates©  Fuzzy Logic   2008 by PhymataSolutions Inc.(Everett Toews) Components   StandardThis presentatio...
Expert Judgment in Groups            Group Review s          Wideband Delphi©What by Phymata Schedule, Features Size, Effo...
Software Estimation Tools            Sof t w are Est im at ion Tools©What by Phymata Schedule, Features   2008     Size, E...
Software Estimation Tools©  Estimation of less common software   2008 by PhymataSolutions Inc.     issues(Everett Toews) ...
Software Estimation Tools©  Data needed to calibrate tools   2008 by PhymataSolutions Inc.(Everett Effort in staff months...
Use of Multiple Approaches©  No single estimation technique is perfect   2008 by PhymataSolutions Inc.   Convergence is ...
Flow of Software Estimates on a         Well-Estimated Project            Changing t o More Accurat e     Est im at e Ref ...
Well Estimated Projects©  Reestimate   2008 by PhymataSolutions Inc.   Refinement(Everett Toews)This presentation may   ...
Standardized Estimation              Procedures©  Protects against   2008 by PhymataSolutions Inc.(Everett Off the cuff e...
Elements of Standardized                 Procedures    Emphasizes counting and computing©2008 by PhymataSolutions Inc. e...
Estimating Size            Funct ion Point s        GUI Elem ent s© What by Phymata  2008      Size, Features           Si...
Estimating Size©  Function Points   2008 by PhymataSolutions Inc.(Everett External Inputs, External Outputs, External    ...
Estimating Effort          I nf ormal Comparison   Est imat ion        I ndust ry Average© 2008 by oPhymata ect s         ...
Estimating Schedule          The Basic Schedule   I nf orm al          Est im at ion Sof t w are          Equation        ...
Schedule Compression    Shortening the schedule increases effort©2008 by Phymata     Trade OffsSolutions Inc.(Everett Sc...
Estimating Planning Parameters©  Estimating total activity   2008 by PhymataSolutions Inc.   Converting estimated effort...
Estimate Presentation Styles©  Communicate estimate assumptions   2008 by PhymataSolutions Inc.   Expressing uncertainty...
Politics, Negotiation and              Problem Solving©  External constraints   2008 by PhymataSolutions Inc.   Negotiat...
Outstanding Issues©  Counting lines of code   2008 by PhymataSolutions Inc.   Estimates vs actual(Everett Toews)This pre...
Recommendations     Developers       Use ranges© 2008 by PhymataSolutions Inc.       Present estimates with assumptions...
Conclusion©  What am I doing about it?   2008 by PhymataSolutions Inc.(Everett Toews) next?   What’sThis presentation ma...
Upcoming SlideShare
Loading in …5
×

The Practice of Software Estimation

545 views
465 views

Published on

A presentation on the practice of software estimation based on the book Software Estimation: Demystifying the Black Art.

Published in: Technology
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
545
On SlideShare
0
From Embeds
0
Number of Embeds
5
Actions
Shares
0
Downloads
22
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

The Practice of Software Estimation

  1. 1. The Practice of Software Estimation © 2008 by Phymata Solutions Inc. (Everett Toews) This presentation may not be modified in any way. Permission to use this presentation is granted toeWorld ES Inc. provided this copyright notice is included.
  2. 2. Presentation Roadmap©  Overview 2008 by PhymataSolutions Inc.  Techniques(Everett Toews)This presentation may  Presentationnot be modified in  Wrap upany way.Permission to use this  Questionspresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  3. 3. Why Talk About Software Estimation?©  My Motivation 2008 by PhymataSolutions Inc.  Advancing the Art and Science of(Everett Toews) Software DevelopmentThis presentation maynot be modified in  Making a livingany way.Permission to use this  My Experiencepresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  4. 4. Current State of Software Estimation©  Most companies looking to avoid 2008 by PhymataSolutions Inc. estimates that are incorrect by 100% or(Everett Toews) moreThis presentation maynot be modified in  Goal – A good estimation approach thatany way. provides estimates that are within 25% ofPermission to use this the actual results %75 of the timepresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  5. 5. Estimates, Targets and Commitments©  Estimate (layman’s definition) – A prediction of 2008 by Phymata how long a project will take or how much it willSolutions Inc. cost.(Everett Toews)This presentation may  Target – A statement of a desirable businessnot be modified in objective.any way.Permission to use this – A promise to deliver defined  Commitment functionality at a specific level of quality on apresentation is certain date.granted toeWorld ES Inc. the target become the estimate  Don’t letprovided thiscopyright notice isincluded.
  6. 6. What is a Good Estimate?  Single point estimates are meaningless© 2008 by PhymataSolutions Inc.(Everett Toews)This presentation maynot be modified inany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided this  All estimates should include a probabilitycopyright notice isincluded.
  7. 7. What is a Good Estimate?©  Making a commitment 2008 by PhymataSolutions Inc.  Ability to support a project’s success(Everett Toews)This presentationproject targets  Realistic maynot be modified in  Estimate – A good estimate is an estimate thatany way.Permission to usea clear enough view of the project provides thispresentation is allow the project leadership to make reality togranted to decisions about how to control the project goodeWorld ES Inc. targets. to hit itsprovided thiscopyright notice isincluded.
  8. 8. How Good an Estimator Are You? 1. Surface temperature of the Sun© 2. Latitude of Shanghai 2008 by PhymataSolutions Inc.of the Asian continent 3. Area(Everett Toews) of Alexander the Great’s birth 4. The yearThis presentation may US currency in circulation in 2004 5. Total value ofnot be modified in 6. Total volume of the Great Lakesany way. 7. Worldwide box office receipts for TitanicPermission to use this 8. Total length of the coastline of the Pacific Oceanpresentation isgrantedNumber of book titles published in the US since 1776 9. toeWorldHeaviest blue whale ever recorded 10. ES Inc.provided thiscopyright notice is Quiz © 2006 Steve McConnellincluded. All Rights Reserved. Permission to copy this quiz is granted provided that this copyright notice is included.
  9. 9. How Good an Estimator Are You? 1. 10,0000F / 6,0000C© 2. 31 Phymata North 2008 by Degrees 17,139,000 miles2 / 44,390,000 km2Solutions Inc. 3.(Everett Toews) 4. 356 BCThis presentation may 5. $719.9 billionnot be modified15in 6. 6 x 10 gallons / 2.3 x 1016 litersany way.Permission to usebillion 7. $1.835 thispresentation is miles / 135,663 kms 8. 84,300granted22 million 9. toeWorld380,000 pounds / 190 tons / 170,000 kgs / 170 10. ES Inc.provided this tons metriccopyright notice is Quiz © 2006 Steve McConnellincluded. All Rights Reserved. Permission to copy this quiz is granted provided that this copyright notice is included.
  10. 10. 90% Confident©  90% confident closer to 30% confident 2008 by PhymataSolutions Inc.(Everett Toews) ranges are more accurate?  NarrowThis presentation may  Pressure to provide narrow ranges is selfnot be modified in inducedany way.Permission to use this  Estimating unknown quantitiespresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  11. 11. Overestimate or Underestimate©  Arguments against overestimation 2008 by PhymataSolutions Inc.  Arguments again underestimation(Everett Toews)This presentation may  Penalty for overestimationnot be modified in  Penalty for underestimationany way.Permission to use thispresentationbest projects come from the most  The is accurate estimatesgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  12. 12. Benefits of Accurate Estimates©  Improved status visibility 2008 by PhymataSolutions Inc.  Higher quality(Everett Toews)  Better coordination with other departmentsThis presentation maynot be modified in  Better budgetingany way.  Increased credibilityPermission to use thispresentation risk info  Early isgranted to  PredictabilityeWorld ES Inc.provided thiscopyright notice isincluded.
  13. 13. The Cone of Uncertainty© 2008 by PhymataSolutions Inc.(Everett Toews)This presentation maynot be modified inany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  14. 14. Where Does Estimation Error Come From?  Chaotic development process©2008 by PhymataSolutions Inc. requirements Unstable(Everett Toews) activities  Omitted  Unfounded optimismThis presentation maynot be modified in & bias  Subjectivity  Off-the-cuff estimatesany way.Permission to use this  Unwarranted precisionpresentation is  Unfamiliar business/technology areagranted to  Simplification of the estimateeWorld ES Inc.  …provided thiscopyright notice isincluded.
  15. 15. Estimate Influences©  Size 2008 by PhymataSolutions Inc.  Diseconomies of scale(Everett Toews)This presentation maynot be modified inany way.Permission to use thispresentation is software being developed  Kind ofgranted to  Personnel factorseWorld ES Inc.  Programming languageprovided thiscopyright notice isincluded.
  16. 16. Estimate Influences© 1. Product complexity 2008 by PhymataSolutions Inc. 2. Requirements analyst capability(Everett Toews)This presentation may 3. Programmer capabilitynot be modified in 4. Time constraintsany way.Permission to use this 5. Personnel continuitypresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  17. 17. Considerations in Choosing Estimation Techniques©  What’s being estimated? 2008 by PhymataSolutions Inc.(Everett Toews) size  ProjectThis presentation may  Development methodologynot be modified in  Development stageany way.Permission to use this  Accuracy possiblepresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  18. 18. Count, Compute, Judge Count Com put e©What by Phymata 2008 Size, Features Size, Effort, Schedule, FeaturesSolutions Inc.M L Size S SM L St age Early-Late(Everett Toews) Early-Middle St yle Iter. & Seq.This presentation may Iter. & Seq. Accuracy High Highnot be modified inany way.Permission to if possible  Count use thispresentation is when you can’t count  Computegranted toeWorld ES judgment alone as a last resort  Use Inc.provided thiscopyright notice isincluded.
  19. 19. What to Count©  Something that is highly correlated 2008 by PhymataSolutions Inc.  Something available sooner than later(Everett Toews)This presentation may  Something that will produce a statisticallynot be modified in meaningful averageany way.Permission to use this  Understand what you are countingpresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  20. 20. Calibration and Historical Data Calibrat e w it h Calibrat ion w it h Calibrat ion w it h© 2008 byI ndust ry Average Dat a Organizat ional Dat a Phymata Proj ect Specif ic Dat aSolutions Inc. Effort, Schedule, Size, Size, Effort, Schedule, Size, Effort, Schedule, What Features Features Features(Everett Toews) Size SM L SM L SM LThis presentation may St age Early-Middle Early-Middle Middle-Latenot yle modifiedSeq. St be Iter. & in Iter. & Seq. Iter. & Seq. Accuracy Low-Medium Medium-High Highany way.  Industry dataPermission to use thispresentation is  Organizational (Historical) datagranted toeWorld ES Inc.data  Projectprovided thiscopyright notice isincluded.
  21. 21. Historical Data©  Accounts for organizational influences 2008 by PhymataSolutions Inc.(Everett Toews)subjectivity, unfounded optimism  Avoids and politicsThis presentation maynot be modified in  Data to collectany way.Permission to use this Time and Defects  Size, Effort,presentation isgranted to to calibrate  HoweWorld ES Inc.provided thiscopyright notice isincluded.
  22. 22. Individual Expert Judgment Use of St ruct ured Use of Est imat ion Est imat ing Task Comparing Task© 2008Process by Phymata Checklist Ef f ort in Ranges Est imat es t o Act uals Effort, Schedule, Effort, Schedule, Size, Effort, Schedule, Size, Effort, Schedule,Solutions Inc.What Features Features Features Features(Everett M LSize S Toews) SM L SM L SM LSt age Early-LateThis presentation may Early-Late Early-Late Middle-LateSt yle Iter. & Seq. Iter. & Seq. Iter. & Seq. Iter. & Seq.not be modified inAccuracy High High High N/ Aany way.Permission to usewhat?  Expert in thispresentation is  Structured expert judgmentgranted to  GranularityeWorld ES Inc.  Checklistprovided thiscopyright notice isincluded.
  23. 23. Use of Ranges©  Single point estimates are bad 2008 by PhymataSolutions Inc.  Best case/Worst case(Everett Toews)This presentation may  Optimistic worst casesnot be modified in  Expected Case = [BestCase + (3 xany way. MostLikelyCase) + (2 x WorstCase)] / 6Permission to use thispresentation is  Task | Best | Most Likely | Worst | Expectedgranted to  RiskeWorld ES Inc.provided thiscopyright notice isincluded.
  24. 24. Compare Estimates to Actuals©  Magnitude of Relative Error = 2008 by PhymataSolutions Inc. (ActualResult - EstimatedResult) /(Everett Toews) ActualResultThis presentation maynot be modified in  Comparisonany way.  FeedbackPermission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  25. 25. Decomposition and Recomposition Decom posit ion by Com put ing Best and© 2008 byDecom posit ion by Phymata Work Breakdow n Worst Cases f rom Feat ure or Task St ruct ure ( WBS) St andard Deviat ionSolutions Inc. Effort, Features What Size, Effort Effort, Schedule(Everett Toews) Size SM L ML SM L St age Early-LateThis presentation may Early-Middle Early-Latenot yle modified Seq. St be Iter. & in Iter. & Seq. Iter. & Seq. Accuracy Medium-High Medium Mediumany way.  DecompositionPermission to use thispresentation is of Large Numbers  The Lawgranted to  Decomposition via WBSeWorld ES Inc.provided this the Best Case and Worst Case  Addingcopyright notice isincluded.
  26. 26. Estimation by Analogy Est imat ion by Analogy©What by Phymata Schedule, Features 2008 Size, Effort,Solutions Inc.M L Size S St age Early-Late(Everett Toews) St yle Iter. & Seq.This presentation may Accuracy Mediumnot be modified inany way.  Simple processPermission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  27. 27. Estimation by Analogy© 1. Similar previous project 2008 by PhymataSolutions Inc. 2. Compare(Everett Toews)This presentation maynot be modifiedup the estimate 3. Build in 4. Create an effort estimateany way.Permission to use this 5. Consistent assumptionspresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  28. 28. Proxy-Based Estimates St andard© 2008FuzzyPhymata by Logic Component s St ory Point s T-Shirt Sizing Size, Effort, Schedule, Effort, Cost, Schedule,Solutions Inc.What Size, Features Size, Effort Features Features(Everett Toews)Size ML SM L SM L MLThis presentation may Early-MiddleSt age Early Early-Middle EarlySt yle Seq. Iter. & Seq. Iter. & Seq. Seq.not be modified inAccuracy Medium Medium Medium-High N/ Aany way.Permission to use thispresentation is proxy  Identifygranted toeWorld ES Inc. or count the proxy  Estimateprovided thiscopyright notice isincluded.
  29. 29. Proxy-Based Estimates©  Fuzzy Logic 2008 by PhymataSolutions Inc.(Everett Toews) Components  StandardThis presentation may  Story Pointsnot be modified in  T-Shirt Sizingany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  30. 30. Expert Judgment in Groups Group Review s Wideband Delphi©What by Phymata Schedule, Features Size, Effort, Schedule, Features 2008 Size, Effort,Solutions Inc. L Size M ML St age Early-Middle(Everett Toews) Early St yle Iter. & Seq.This presentation may Seq. Accuracy Medium Mediumnot be modified inany way.Permission to Reviews  Group use thispresentation is  Wideband Delphigranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  31. 31. Software Estimation Tools Sof t w are Est im at ion Tools©What by Phymata Schedule, Features 2008 Size, Effort,Solutions Inc.L Size M St age Early-Middle(Everett Toews) St yle Iter. & Seq.This presentation may Accuracy Highnot be modified inany way.Permission to useproject outcomes  Simulate thispresentation is  Probability analysisgranted toeWorld ES Inc. for diseconomies of scale  Accountprovided this for creeping requirements  Accountcopyright notice isincluded.
  32. 32. Software Estimation Tools©  Estimation of less common software 2008 by PhymataSolutions Inc. issues(Everett Toews)  Planning options and tool integrationThis presentation maynot be modified in  What-if analysisany way.Permission to use this  Referee unrealistic project expectationspresentation is  Objective authoritygranted toeWorld ES Inc.provided this checking manual estimates  Sanitycopyright notice is large projects  Estimatingincluded.
  33. 33. Software Estimation Tools©  Data needed to calibrate tools 2008 by PhymataSolutions Inc.(Everett Effort in staff months  Toews)  ScheduleThis presentation maynot be modified inany way.Size in LOC   Available toolsPermission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  34. 34. Use of Multiple Approaches©  No single estimation technique is perfect 2008 by PhymataSolutions Inc.  Convergence is good, spread is bad(Everett Toews)This presentation may  Misconceptionsnot be modified in  Different resultsany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  35. 35. Flow of Software Estimates on a Well-Estimated Project Changing t o More Accurat e Est im at e Ref inem ent Based© 2008 by Phymata Lat er in t he Met hods on Proj ect -Specif ic Dat aSolutions Inc. Effort, Schedule, Features What Size, Size, Effort, Schedule, Features Size ML(Everett Toews) SM LThisage St presentation may Early-Late Early-Late St yle Seq. Seq.not be modified in Accuracy High Highany way.  Poorly estimated projectsPermission to use thispresentationestimated projects  Well isgranted to  Size > Effort > Schedule | Cost | FeatureseWorld ES Inc.provided thiscopyright notice isincluded.
  36. 36. Well Estimated Projects©  Reestimate 2008 by PhymataSolutions Inc.  Refinement(Everett Toews)This presentation may  Make up the timenot be modified inany way.Add the time Permission to use this whole schedule by the magnitude  Multiply thepresentation is of the slipgranted to  Presenting reestimationeWorld ES Inc.provided thiscopyright notice isincluded.
  37. 37. Standardized Estimation Procedures©  Protects against 2008 by PhymataSolutions Inc.(Everett Off the cuff estimates  Toews)  GuessingThis presentation maynot be modified inany way.Changing the estimate because a stakeholder Permission to use this it doesn’t like  Encourage consistencypresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  38. 38. Elements of Standardized Procedures  Emphasizes counting and computing©2008 by PhymataSolutions Inc. estimation approaches Multiple  Reestimation(Everett Toews)  Approach changes over the course of a projectThis presentation may  Clear description of estimate’s inaccuracynot be modified in  When it can be used as a basis for internal andany way. external commitmentsPermission to use thispresentation is estimation data for later review  Archivinggranted to  Deviations should be documented and rareeWorld ES Inc.provided this when estimation occurs in SDLC  Definecopyright notice isincluded.
  39. 39. Estimating Size Funct ion Point s GUI Elem ent s© What by Phymata 2008 Size, Features Size, FeaturesSolutions Inc.M L Size S SM L St age Early-Middle(Everett Toews) EarlyThisyle St presentation may Seq. Seq. Accuracy High Lownot be modified inany way.Permission to use this in size estimation  Role of LOCpresentation isdimension  Singlegranted toeWorld ES Inc. measure something  Have toprovided thiscopyright notice isincluded.
  40. 40. Estimating Size©  Function Points 2008 by PhymataSolutions Inc.(Everett External Inputs, External Outputs, External  Toews) Queries, Internal Logical Files, ExternalThis presentation maynot be modified in Files Interfaceany way.  GUI ElementsPermission to use this  Screens, Reports, Files, Interfaces, Dialogspresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  41. 41. Estimating Effort I nf ormal Comparison Est imat ion I ndust ry Average© 2008 by oPhymata ect s t Past Proj Sof t w are Tools Ef f ort GraphsSolutions Effort What Inc. Effort Effort Size SM SM L SM(Everett Toews) St age Early-Middle Early-Middle EarlyThis presentation may St yle Iter. & Seq. Iter. & Seq. Seq.not be modified in Accuracy Medium High Low-Mediumany way.  Informal ComparisonPermission to use thispresentation is  Estimation Software Toolsgranted toeWorld ES Inc. Average Effort Graphs  Industryprovided thiscopyright notice isincluded.
  42. 42. Estimating Schedule The Basic Schedule I nf orm al Est im at ion Sof t w are Equation Com parison t o Past Tools What Schedule© 2008 by Phymata Schedule Schedule Size ML SM L MLSolutions Early St age Inc. Early Early(Everett Toews) St yle Seq. Iter. & Seq. Iter. & Seq. Accuracy MediumThis presentation may Medium Highnot be modified in Schedule Equation  The Basicany way.ScheduleInMonths = 3.0 x StaffMonths1/3 Permission to use this  Informal Comparison to Past Projectspresentation is  EstimatedSchedule = PastSchedule xgranted to (EstimatedEffort / PastEffort)1/3eWorld ES Inc.  Estimation Software Toolsprovided thiscopyright notice isincluded.
  43. 43. Schedule Compression  Shortening the schedule increases effort©2008 by Phymata Trade OffsSolutions Inc.(Everett Schedule | Effort  Toews)This presentation may+100%  -15% |not be -10% | +50% modified inany way.Permission to use this+25%  -5% | 0%presentation is  | 0%  Team Sizegranted toeWorld ES Inc.providedAverageTeamSize = EffortEstimate /  this Schedulecopyright notice isincluded.
  44. 44. Estimating Planning Parameters©  Estimating total activity 2008 by PhymataSolutions Inc.  Converting estimated effort to(Everett Toews) planned effortThis presentation maynot be modified in  Estimating defect production and removalany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  45. 45. Estimate Presentation Styles©  Communicate estimate assumptions 2008 by PhymataSolutions Inc.  Expressing uncertainty(Everett Toews)This presentation may  Risk qualificationnot be modified in  Accuracyany way.Permission to use this  Rangespresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  46. 46. Politics, Negotiation and Problem Solving©  External constraints 2008 by PhymataSolutions Inc.  Negotiating a commitment(Everett Toews)This presentation may  Problem solvingnot be modified inany way.Separate the people from the problem Permission to use this  Focus on interests, not positionspresentation is  Invent options for mutual gaingranted toeWorld ES Inc. on using objective criteria  Insistprovided thiscopyright notice isincluded.
  47. 47. Outstanding Issues©  Counting lines of code 2008 by PhymataSolutions Inc.  Estimates vs actual(Everett Toews)This presentation may  Contractual software developmentnot be modified inany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.
  48. 48. Recommendations  Developers  Use ranges© 2008 by PhymataSolutions Inc.  Present estimates with assumptions(Everett Toews)  ManagementThis presentation maynot be Use historical data modified inany way.Archive estimates in an easily accessible place Permission to usea standardized estimation procedure  Publish thispresentation is  Bothgranted to  Use checklistseWorld ES Inc.providedphymata.blogspot.com  thiscopyright notice isincluded.
  49. 49. Conclusion©  What am I doing about it? 2008 by PhymataSolutions Inc.(Everett Toews) next?  What’sThis presentation may  construx.com/Page.aspx?nid=297not be modified inany way.Permission to use thispresentation isgranted toeWorld ES Inc.provided thiscopyright notice isincluded.

×