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Estimation and Trust

Estimation and Trust

From Ancient City Ruby 215

Noel Rappin

March 27, 2015
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  1. Intentionally Vague Slide Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  2. How far do you live from an airport? Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  3. I live !" minutes from one Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  4. If I'm in a car And the weather is good

    And it's not rush hour And I don't blow a tire Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  5. Failing any of these makes my trip longer Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  6. Estimation and Trust Noel Rappin, Table XI Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  7. I am an idiosyncratic crank about estimates Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  8. Are software developers uniquely bad at estimates? Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  9. Ever done a home remodel? Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  10. Big Dig Noel Rappin, Estimates and Trust, Ancient City Ruby

    2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  11. Initial cost estimate $5.8 billion !!!!!! Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  12. Final cost: $21.93 billion And counting... !!!!!!!!!!! !!!!!!!!!!! Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  13. It's not just our problem Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  14. Why do we need to estimate? Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  15. What about #noestimates? Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  16. I'll stop estimating when my clients stop asking Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  17. Communication Noel Rappin, Estimates and Trust, Ancient City Ruby 2015.

    http://www.noelrappin.com http://www.tablexi.com @noelrap
  18. Estimating Projects: Communicates client investment Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  19. Estimating Projects: Allows us to gauge progress Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  20. Estimating Projects: Enables us to think about the problem Noel

    Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  21. Estimating Projects Badly: Sets unrealistic expectations Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  22. Estimating Projects Badly: Encourages micromanaging Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  23. Estimating Projects Badly: Stops us from thinking about the problem

    Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  24. Estimating at the beginning is the worst Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  25. Like guessing time to the airport if you don't even

    know where the airport is Or if you even need to fly... Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  26. How can we estimate Effectively? Ethically? Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  27. Estimating projects vs. Estimating features Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  28. Nobody really cares about estimating features Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  29. They only care about when users can use stuff Noel

    Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  30. Feature estimates are only useful to get you to project

    estimates Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  31. A quick sidebar of agile terms Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  32. Feature Story Iteration Point Velocity Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  33. Kind of a theory of ethical estimates Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  34. Estimates are estimates Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  35. Estimates are probabilistic Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  36. Chance of rain: 50% ☔ Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  37. We can make bad assumptions Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  38. Misunderstanding the problem Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  39. Scope Creep Noel Rappin, Estimates and Trust, Ancient City Ruby

    2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  40. Unknown complexity Noel Rappin, Estimates and Trust, Ancient City Ruby

    2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  41. Rework Noel Rappin, Estimates and Trust, Ancient City Ruby 2015.

    http://www.noelrappin.com http://www.tablexi.com @noelrap
  42. Political issues Optimism Pressure Noel Rappin, Estimates and Trust, Ancient

    City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  43. Can we do better? Noel Rappin, Estimates and Trust, Ancient

    City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  44. Focus on what we're good at Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  45. Avoid false precision Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  46. What goes into the amount of calendar time a feature

    takes? Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  47. Complexity of the task Skill of the developer Time on

    task Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  48. We are bad at estimating time on task Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  49. But it tends to be consistent over time Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  50. Skill of the developer Noel Rappin, Estimates and Trust, Ancient

    City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  51. We're also not that great at estimating this Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  52. And it's toxic Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  53. But it tends to be consistent over time Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  54. We are pretty good at estimating complexity Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  55. Which is to say ! ⚪ ! Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  56. Estimate complexity and let time sort itself out Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  57. Which is like basing our airport estimate on: Distance to

    airport Average speed in the past Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  58. Consistency Noel Rappin, Estimates and Trust, Ancient City Ruby 2015.

    http://www.noelrappin.com http://www.tablexi.com @noelrap
  59. Of team size Of story makeup Of environment Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  60. Decomposing the problem into similar size chunks helps Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  61. Requires Time Noel Rappin, Estimates and Trust, Ancient City Ruby

    2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  62. How do I estimate at the beginning of a project?

    Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  63. The worst way to estimate (except for all the other

    ways) Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  64. Fake it Noel Rappin, Estimates and Trust, Ancient City Ruby

    2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  65. Don't fake knowledge or precision Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  66. Realize that your output is a range Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  67. Split the tasks as best you can Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  68. Assign points 1: easy, less than a day 3: has

    complexity or risk 5: has a lot more complexity or risk Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  69. Don't spend a lot of time assigning points to a

    single task Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  70. Round up Noel Rappin, Estimates and Trust, Ancient City Ruby

    2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  71. At the beginning (and only at the begining) You can

    range estimate stories Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  72. Range of points Noel Rappin, Estimates and Trust, Ancient City

    Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  73. load factor (5 - 7 hours per point) Noel Rappin,

    Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  74. Low point total * low factor High point total *

    high factor Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  75. points * factor = hours hours * rate = estimate

    Noel Rappin, Estimates and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  76. Present this with humility Noel Rappin, Estimates and Trust, Ancient

    City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  77. Understand that this will change Noel Rappin, Estimates and Trust,

    Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  78. You are headed to the airport together Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  79. Thanks Image credits 4 http://www.constructionequipmentguide.com/ historical/big-dig/ Noel Rappin, Estimates and

    Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap
  80. Noel Rappin Table XI @noelrap http://www.noelrappin.com/trdd http://pragprog.com/book/nrtest2 Noel Rappin, Estimates

    and Trust, Ancient City Ruby 2015. http://www.noelrappin.com http://www.tablexi.com @noelrap