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Todd Little

Uncertainty Surrounding the Cone of Uncertainty. Todd Little. IEEE Software, May/June 2006. Managing the Coming Storm Inside the Tornado. When will we get the requirements?. All in good time, my little pretty, all in good time. But I guess it doesn't matter anyway.

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Todd Little

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  1. Uncertainty Surrounding the Cone of Uncertainty Todd Little

  2. IEEE Software, May/June 2006

  3. Managing the Coming Storm Inside the Tornado When will we get the requirements? All in good time, my little pretty, all in good time But I guess it doesn't matter anyway Just give me your estimates by this afternoon Not so fast! Not so fast! ... I'll have to give the matter a little thought. Go away and come back tomorrow No, we need something today! Ok then, it will take 2 years. No, we need it sooner. Doesn't anybody believe me? I already promised the customer it will be out in 6 months You're a very bad man! Project Kickoff Team Unity

  4. We’re not in Kansas Anymore I may not come out alive, but I'm goin' in there! The Great and Powerful Oz has got matters well in hand. My! People come and go so quickly here! "Hee hee hee ha ha! Going so soon? I wouldn't hear of it! Why, my little party's just beginning! Developer Hero Reorg Testing

  5. The Cone of Uncertainty (Boehm) 2 0.5 Cone of Uncertainty: The amount of possible error in a software project estimate, which is very large in the early stages of a project and shrinks dramatically as the project nears completion – Steve McConnell

  6. Hurricane Rita

  7. Landmark Product Suite Reservoir / Fluid data Seismic data Production data Structural / Stratigraphic data Common Model Representation Common Model Representation Velocity data Well data Geophysics Engineering Geology

  8. Data from LGC

  9. Data from Tom DeMarco It’s déjà vu all over again

  10. Cumulative Distribution Curve for Actual/Estimate (DeMarco)

  11. CDF Distribution Curve (LGC)

  12. Probability Distribution Curve

  13. Log Normal Distribution Mean Median • Estimation Accuracy follows a Log Normal distribution

  14. “It’s tough to make predictions, especially about the future.”Yogi Berra, Niels Bohr That idea is so damned nonsensical and impossible that I'm willing to stand on the bridge of a battleship while that nitwit tries to hit it from the air. Newton Baker, U.S. secretary of war in 1921, reacting to the claim of Billy Mitchell (later Brigadier General Mitchell) that airplanes could sink battleships by dropping bombs on them.

  15. “It’s tough to make predictions, especially about the future.”Yogi Berra, Niels Bohr Heavier-than-air flying machines are impossible. Lord Kelvin, British mathematician, physicist, and president of the British Royal Society, spoken in 1895.

  16. How does Estimation Accuracy Improve Over Time? (Boehm) 2 0.5

  17. So what does LGC data look like?

  18. Landmark Cone of Uncertainty

  19. But is Uncertainty Really Reduced? “Take away an ordinary person’s illusions and you take away happiness at the same time.” Henrik Ibsen--Villanden

  20. Cumulative Distribution (CDF) Curve

  21. Remaining Uncertainty

  22. The Pipe of Uncertainty 2 0.5

  23. Does Landmark Suck at Estimation? A severe depression like that of 1920-21 is outside the range of probability. Harvard Economic Society, Weekly Letter, November 16, 1929.

  24. Does Landmark Suck at Estimation? I think there is a world market for about five computers. Thomas J. Watson, chairman of IBM, 1943.

  25. Does Landmark Suck at Estimation? They couldn't hit an elephant at this dist… General John B. Sedgwick, Union Army Civil War officer's last words, uttered during the Battle of Spotsylvania, 1864

  26. Estimation Quality Factor (EQF) Actual Value Blue Area Red Area Value to be Estimated EQF = Initial Estimate Actual End Date Elapsed Time Link to article by Tim Lister

  27. EQF from Lister/DeMarco

  28. EQF Distribution Curve (LGC) EQF for duration has a theoretical minimum of 2.0

  29. We slip one day at a time, EQF=2 Actual Value Blue Area Red Area Value to be Estimated EQF = Initial Estimate Actual End Date Elapsed Time

  30. (EQF-2) Distribution Curve (LGC data)

  31. From the home office in Duncan, Oklahoma Dubai, UAE Top Ten reasons why we are late in 2008 Top 10 List Top 10 List

  32. Top Ten reasons why we are late in 2008 10: Requirements, what Requirements? • What you want, baby I got it R-E-Q-U-I-R-E Find out what it means to me

  33. Top Ten reasons why we are late in 2008 9: Dependencies on other groups that were late

  34. Top Ten reasons why we are late in 2008 LIFE OF SOFTWARE 8: Over-optimistic Schedule Estimation Always look on the bright side of code . . . . . . . Always look on the bright side of code . . . . . . . The code’s a piece of $#!^, when we look at it We can always overlook a minor kink . . . . It probably compiles, it might even link . . . Surely that must mean it doesn’t stink

  35. Top Ten reasons why we are late in 2008 7: Those weren’t MY estimates Scheduling Ritual How low can you go!

  36. Top Ten reasons why we are late in 2008 6: Not enough testers or documentation resources. Who needs them anyway? We put those bugs--I mean features--in there on purpose. Besides, it was difficult to program, it should be difficult to use.

  37. Top Ten reasons why we are late in 2008 5: Offshore and Outsourcing issues My source code lies over the ocean, My source code lies over the sea . My source code lies over the ocean, Oh bring back my source code to me . . . . . Bring Back, Bring Back, oh bring back my source code to me, to me Bring Back, Bring Back, oh bring back my source code to me

  38. Top Ten reasons why we are late in 2008 4: One word, Ch-ch-ch-changes

  39. Top Ten reasons why we are late in 2008 3: I can’t get no, System Admin • I can’t get no, CM action • ‘cause I try, • ..and I try, • ….and I try, • ……and I try….

  40. Top Ten reasons why we are late in 2008 2: You didn’t give me the headcount that you promised

  41. Top Ten reasons why we are late in 2008 1: Weren’t you doing the backups!?

  42. You can get better

  43. How to get better • Start Measuring • Understand bias • Collaborate • Manage Uncertainty

  44. Start Measuring

  45. Understand Bias • "What gets us into trouble is not what we don't know. It's what we know for sure that just ain't so.“ • Mark Twain

  46. Uncertainty Know that we know Know that we don’t know Knowable Unknowable Don’t know that we know Don’t know that we don’t know

  47. Uncertainty Know that we know Planning p10 Know that we don’t know Risk Management p50 Knowable Unknowable Don’t know that we know Don’t know that we don’t know Uncertainty Management p90

  48. Just Double the Estimate

  49. Defending an Unpopular Schedule • Developers tend to be temperamentally opposed to the use of negotiating tricks. Such tricks offend their sense of technical accuracy and fair play. Developers don't want to offer lopsidedly high initial estimates even when they know that customers, marketers, or bosses will start with lopsidedly low bargaining positions. • Steve McConnell http://www.stevemcconnell.com/ieeesoftware/bp03.htm

  50. We want this Innovation Revenue Predictability Efficiency SOA Software as a Service Late projects Web Services Integration ERP Web Portal BPM Agile

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