Lies, damn lies, estimates

1. ©ClaysnowLimited2014 Lies, damn lies and estimates Seb Rose Claysnow Limited www.claysnow.co.uk @sebrose Tuesday, 15 April 14

2. ©ClaysnowLimited2014 Tuesday, 15 April 14

3. ©ClaysnowLimited2014 DISRAELI Tuesday, 15 April 14

9. ©ClaysnowLimited2014 I’ll be back tomorrow to finish off You’ll be in by Christmas That will be fixed before we leave All our previous customers are completely satisfied We don’t make mistakes like other builders You won’t notice we’re there Tuesday, 15 April 14

10. ©ClaysnowLimited2014 Your company NEEDS that estimate soonnowyesterday (Of course we won’t hold you to it) Tuesday, 15 April 14

11. ©ClaysnowLimited2014 The project status is still green We’re 90% done We will deliver with zero defects On time, on budget every project It’s working in the test environment Integration takes hardly any time Tuesday, 15 April 14

12. ©ClaysnowLimited2014 Prediction is very difﬁcult, especially about the future. Niels Bohr, physicist Tuesday, 15 April 14

14. ©ClaysnowLimited2014 The primary purpose of an estimate is not to predict a project’s outcome; it is to determine whether a project’s targets are realistic enough to allow the project to be controlled to meet them. Steve McConnell, Software Estimation (2006) Tuesday, 15 April 14

15. ©ClaysnowLimited2014 6. Introduction to Estimation Techniques 7. Count, Compute, Judge 8. Calibration and Historical Data 9. Individual Expert Judgement 10. Decomposition and Recomposition 11. Estimation by Analogy 12. Proxy-Based Estimates 13. Expert Judgement in Groups 14. Software Estimation Tools 15. Use of Multiple Approaches 16. Flow of Software Estimates on a Well- Estimated Project 17. Standardized Estimation Procedures Part II - Fundamental Estimation Techniques Tuesday, 15 April 14

18. ©ClaysnowLimited2014 The Cone of Uncertainty in Project Management Tuesday, 15 April 14

20. ©ClaysnowLimited2014 Overconﬁdence Tuesday, 15 April 14

21. ©ClaysnowLimited2014 For each of the next 10 quantitative questions, give a lower and an upper bound, such that you believe with about 90% certainty that the correct answer lies within the interval given. This means that you should expect to guess correctly for about 9 questions out of 10. Laurent Bossavit, www.bossavit.com, @morendil Tuesday, 15 April 14

22. ©ClaysnowLimited2014 Example: Q. How many people are in this room? You ‘guess’ an interval: Low: 30, High: 100 Tuesday, 15 April 14

23. ©ClaysnowLimited2014 What was the date of birth of Bram Stoker, author of Dracula? Question 1: Tuesday, 15 April 14

24. ©ClaysnowLimited2014 What is the population of the Republic of Brazil? Question 2: Tuesday, 15 April 14

25. ©ClaysnowLimited2014 What is the height, in meters, of the tallest living redwood tree? Question 3: Tuesday, 15 April 14

26. ©ClaysnowLimited2014 How many standardized (ISO 6346) steel shipping containers exist in the world? Question 4: Tuesday, 15 April 14

27. ©ClaysnowLimited2014 How many Boeing 747 (all models) have been built at this date? Question 5: Tuesday, 15 April 14

28. ©ClaysnowLimited2014 What is the total number of human deaths attributed to H5N1 “avian” ﬂu? Question 6: Tuesday, 15 April 14

29. ©ClaysnowLimited2014 How many Syrian conﬂict refugees were registered by UNHCR as of 1 Nov 2012? Question 7: Tuesday, 15 April 14

30. ©ClaysnowLimited2014 What was the total wine production of France in 2009, in hectolitres? Question 8: Tuesday, 15 April 14

31. ©ClaysnowLimited2014 How many Olympics medals altogether have been won to date by Austrian athletes? Question 9: Tuesday, 15 April 14

32. ©ClaysnowLimited2014 What is the half-life, in years, of the isotope Plutonium 239? Question 10: Tuesday, 15 April 14

33. ©ClaysnowLimited2014 1) 1847 2) 199 million 3) 115 meters 4) 20 million 5) 1486 6) 379 7) 286,000 8) 45 million hectolitres 9) 304 10) 24 thousand years Tuesday, 15 April 14

34. ©ClaysnowLimited2014 How did you do? Tuesday, 15 April 14

35. ©ClaysnowLimited2014 "We aren't really bad at estimating. What we are really bad at is enumerating all the assumptions that lie behind our estimates." -Paul Rook Tuesday, 15 April 14

36. ©ClaysnowLimited2014 Why do we estimate? Tuesday, 15 April 14

37. ©ClaysnowLimited2014 Forecasting Tuesday, 15 April 14

38. ©ClaysnowLimited2014 Tracking Tuesday, 15 April 14

40. ©ClaysnowLimited2014 “A boundary object is a concept in sociology to describe information used in different ways by different communities. They are plastic, interpreted differently across communities but with enough immutable content to maintain integrity” --Wikipedia Estimates are Boundary Objects Tuesday, 15 April 14

41. ©ClaysnowLimited2014 “They are weakly structured in common use, and become strongly structured in individual-site use. They may be abstract or concrete. They have different meanings in different social worlds but their structure is common enough to more than one world to make them recognizable means of translation. The creation and management of boundary objects is key in developing and maintaining coherence across intersecting social worlds.” -- Leigh & Griesemer Tuesday, 15 April 14

42. ©ClaysnowLimited2014 http://leadinganswers.typepad.com/leading_answers/ﬁles/original_waterfall_paper_winston_royce.pdf The original “waterfall” paper - Winston Royce, 1970 Tuesday, 15 April 14

47. ©ClaysnowLimited2014 How long is a piece of string? Tuesday, 15 April 14

49. ©ClaysnowLimited2014 120 cm 100 cm 70 cm 60 cm 40 cm E. D. C. A. B. Tuesday, 15 April 14

50. ©ClaysnowLimited2014 ... these studies which have for a few years now given rise to the claim that "research shows that people are better at relative than absolute estimation" do not in fact seem to square with that claim. This doesn't entail that relative estimation doesn't work - only that it is not proven. http://guide.agilealliance.org/guide/relative.html Tuesday, 15 April 14

52. ©ClaysnowLimited2014 12 cm 10 cm 7 cm 6 cm 4 cm E. D. C. A. B. Tuesday, 15 April 14

53. ©ClaysnowLimited2014 Is it small, or just far away? Tuesday, 15 April 14

55. ©ClaysnowLimited2014 winnipegagilist.blogspot.com Tuesday, 15 April 14

56. ©ClaysnowLimited2014 “If a project has no risks, don’t do it.” “Waltzing with bears”, DeMarco & Lister, 2003 Tuesday, 15 April 14

57. There are known knowns; there are things we know that we know. There are known unknowns; that is to say there are things that, we now know we don't know. But there are also unknown unknowns – there are things we do not know we don't know. Tuesday, 15 April 14

58. ASSUME YOU'RE IGNORANT Tuesday, 15 April 14

59. ©ClaysnowLimited2014 “... during an inception, when we are most ignorant about most aspects of the project, the best use we can possibly make of the time available is to attempt to identify and reduce our ignorance” http://dannorth.net/2010/08/30/introducing-deliberate-discovery/ Deliberate discovery Tuesday, 15 April 14

60. ©ClaysnowLimited2014 1. Just about everyone in the world has done this. 2. Lots of people have done this, including several people in the company. 3. Someone in our company has done this. 4. Someone in the world did this, but not in our organisation (and probably at a competitor). 5. Nobody has ever done this before. http://lizkeogh.com/2013/07/21/estimating-complexity/ Estimating Complexity Tuesday, 15 April 14

66. ©ClaysnowLimited2014 Cost of delay http://blackswanfarming.com/cost-of-delay/ ... is a way of communicating the impact of time on value. Tuesday, 15 April 14

67. ©ClaysnowLimited2014 Cost of delay http://blackswanfarming.com/cost-of-delay/ 1.Better Decision-making – by making the economic trade-offs visible 2.Better Prioritisation – by using CD3 (Cost of Delay Divided by Duration) we deliver more total value 3.By changing the focus – from efﬁciency and cost (which encourages the wrong behaviours), to speed and value Tuesday, 15 April 14

68. ©ClaysnowLimited2014 #NoEstimates http://neilkillick.com/2013/02/08/noestimates-part-2-contract-negotiation-and-the-old-banger/ http://neilkillick.com/2013/01/31/noestimates-part-1-doing-scrum-without-estimates/ Remove the unknowns Estimating sprint velocity is waste Iterate, don’t estimate Shift focus to “small” Agile team, same old contract Quality is variable, not ﬁxed Don’t deliver requirements, deliver what the customer wants Tuesday, 15 April 14

69. ©ClaysnowLimited2014 ... crying “No estimates, no backlogs, no deadlines” ... [is] not very effective nor efﬁcient. http://xprogramming.com/articles/artifacts-are-not-the-problem/ Tuesday, 15 April 14

70. ©ClaysnowLimited2014 Done conventionally, software projects offer almost no information, and almost no control, to those who are given the responsibility to manage them. ... the people in charge of spending money to get software really do need control and information. Saying “no” doesn’t help them. http://xprogramming.com/articles/artifacts-are-not-the-problem/ Tuesday, 15 April 14

71. ©ClaysnowLimited2014 Giving software projects an API ... [is] about “yes, yes, yes”. http://xprogramming.com/articles/artifacts-are-not-the-problem/ Tuesday, 15 April 14

73. ©ClaysnowLimited2014 Dear Customer ... when we start an IT project, we don’t know how much time and effort it will take to complete. Consequently, we don’t know how much it will cost. http://www.agileconnection.com/article/dear-customer-truth-about-it-projects?page=0%2C0 Tuesday, 15 April 14

74. ©ClaysnowLimited2014 Dear Customer http://www.agileconnection.com/article/dear-customer-truth-about-it-projects?page=0%2C0 ... the more details you try to give us beforehand, the more likely your desires are to change. Each time you give us more detail, you are offering more hostages to fortune. Tuesday, 15 April 14

75. ©ClaysnowLimited2014 “Old fogies know your estimates will be bogus. They know you won’t get them right. They know you won’t hit the deadline with full scope” http://xprogramming.com/articles/artifacts-are-not-the-problem/ Tuesday, 15 April 14

76. ©ClaysnowLimited2014 Challenge the use of estimates - understand its value Estimates are not commitments - make this crystal clear Is it small or just far away - ignorance is the major constraint Take aways Tuesday, 15 April 14

78. Seb Rose Twi$er: @sebrose Blog: www.claysnow.co.uk E-‐mail: seb@claysnow.co.uk Tuesday, 15 April 14

79. ©ClaysnowLimited2014 Estimates produced before a project starts are lies about how much something will cost, usually tailored depending on whether the source of the estimate wants the project to go ahead or not. Estimates produced once a project has started are lies that compensate for the inaccuracies of earlier estimates. Both contribute towards an illusion of control that is no more real in software than it is in civil engineering. http://accu.org/index.php/journals/1836 Tuesday, 15 April 14

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