Estimation Approaches for the Scrum Team.

Naveen Kumar Singh
3 min readApr 13, 2024
Estimation

Hello, and welcome to the world of Scrum. Scrum is a framework that helps organizations manage complex projects, and today, we’ll explore one of its key elements: Estimation.

Imagine you estimated you would read a 500-page book in 4 days, but you took over a week to finish. Is this an example of the wrong estimation?

In the business world, be it software development, budget planning, or market research, estimations may need to be updated as and when teams learn more about the work. The main reasons behind wrong estimates or variance in estimates are uncertainty and the complexity of the work.

You can easily estimate the efforts and time needed for independent repetitive work with known complexity. However, this is different when developing an application or a product. As a result, you will overestimate or underestimate your work, which is okay, but it might be challenging to forecast.

The team adopts agile and scrum practices to deal with uncertainty and complexity because they help improve predictability with frequent inspection and adaptation cycles. But this doesn’t mean we don’t need estimation. In fact, estimation in Scrum has become more challenging because the team has to provide estimates rather than individual ones.

In Scrum, the team is responsible for finding an approximation or estimate of the amount of effort and time required to complete a task, also called a User Story in many organizations. These estimations are necessary for planning Sprints and figuring out how much a team can handle.

The scrum team follows different estimation techniques to provide the right estimation. One such technique is Story Points.

In this method, numbered coded cards are distributed among each scrum team member. The team uses these cards to estimate the effort needed for each user story. The card with the highest voting gets finalized to plan sprints and decide how much the team can work. Most teams use Fibonacci series numbers on these cards or modified Fibonacci series numbers like 1,2,3,5,8,13,20,40,100. Some teams even use ½ or 0.

Another popular estimation technique is- estimation by analogy. Teams struggle with absolute estimates, but they can be accurate if they use the relative sizing approach for estimation. Again, the team usages very small, small, medium, large, and very large kinds of concepts. For example, a team has already estimated a user story to be two weeks. Now, if the team comes across another user story twice as large as the already estimated user story, they’ll allocate a larger estimation number to finish the task. The estimation using analogy technique is widely used among highly experienced agile teams.

The t-shirt size estimation technique is equally popular in the agile world. In this method, the user stories are estimated in t-shirt sizes: XS, S, M, L, and XL. The sizes here represent the complexity and needed effort for each story.

So, your team can categorize each user story under different t-shirt sizes based on their effort and complexity.

There are some other techniques that you can try, like Same Size Story or Right Size Story. We at Agilemania follow the Same Size Story, so we just count rather than estimate. This is not for you if you love Sprint Burndown charts using story points.

So, what are the benefits of running an agile estimation process in your organization?

  1. Estimations can make your team accountable for deliverables
  2. With estimation, the team can plan a better sprint, make better decisions, and deliver user stories in a timely
  3. Estimation induces discipline across the team and increases productivity.
  4. Predicting the time and effort needed to finish a project will improve predictability.

I hope it helped you understand the importance of estimation in the scrum. Stay tuned to learn more scrum elements from our team.

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Naveen Kumar Singh

Agile Coach and Professional Scrum Trainer (PST) @Agilemania, Servant leader @Agile 30 and Developer @GitHub, Ranting @LinkedIn & an Artist @YouTube