Estimating tasks, activities, projects

• Fundamentals

• What works

• Why do things go wrong

• Questions & Answers


• Fundamentals

• What works

• Why do things go wrong

• Questions & Answers


• An estimate is really just a guess.

• Yet, we have to negotiate expectations for accuracy.

  • I’ll check in the unit tests by noon
  • I’ll have the search feature implemented by Friday
  • We will have the project done in December

• Why do we need to estimate?

  • We need to set expectations
  • We need to allocate time and resources
  • Other tasks depending on its completion
  • We need to make better estimates in the future

• Effort can be structured based on the visibility of results.

  • Tasks – an effort that produces an identifiable and valuable output
  • Activities – a sequence of tasks 
  • Projects – a complex sequence of activities

• Estimation with any accuracy gets increasingly hard, perhaps impossible for certain processes.

  • Complex projects
  • Changes in requirements or resources
  • Innovation

• Projects are seen to fail or succeed based on the accuracy of the initial estimates.

How we estimate

• Comparison– this task is similar to another task I completed

• Ranking – this task is harder (or easier) than another task

• Coercion– we are told how long a task will take

• Time-boxing – I can allocate only this amount of time

• We often neglect our experience in estimating tasks.

  • Estimates express ‘ideal’ time and effort
  • Communication
  • Meetings
  • Set up and tear-down
When estimating tasks, activities, and/or projects, how do we end up being so wrong?