Relative estimation is a technique I have extensively used to tackle complex problems. It offers a flexible approach to estimating the relative size of the work to be done by breaking it down into smaller tasks. At the core of this method lies the comparison of perceived effort for each task, rather than getting lost in absolute estimates.
One of the most well-known methods for relative estimation is Story Points, where my team and I assign points to each task or feature based on their perceived complexity. Story Points are not tied to a specific unit of time but instead represent complexity, effort, and required work. This estimation is usually based on a common repository of tasks previously completed by the team, using comparison and past experience.
Another widely used technique for relative estimation is Poker Planning, also known as “planning poker.” In this method, team members are given a set of cards with numerical values (e.g., 1, 2, 3, 5, 8, 13, 20, etc.). During estimation, each member selects a card to represent the complexity of the task or feature under evaluation, and then all members reveal their cards simultaneously. In case of significant discrepancies, we discuss the reasons behind our estimates before repeating the process until a consensus is reached.
However, this method can seem challenging to implement, which is why we explored other approaches to help us get started and practice until our team felt comfortable with using Story Points:
T-shirt planning or T-shirt sizing
In this method, each team member is assigned a set of T-shirt sizes representing different levels of complexity, from XS (Extra Small) for simple tasks to XL (Extra Large) for highly complex ones.
This technique is similar to Story Points and T-shirt planning, but it uses categories called “buckets” to classify items based on their level of difficulty or complexity, e.g., “Easy,” “Medium,” “Difficult,” “Very Difficult,” etc.
Another playful approach is to use fruit sizes (small, medium, large, etc.) to represent the complexity of tasks. For example, a simple task might be compared to a cherry (small), while a complex task could be associated with a watermelon (large).
To express different levels of complexity, we can use movie star ratings (one star, two stars, three stars, etc.) to estimate items.
Whichever method of relative estimation you choose, it’s crucial that the entire team understands the scoring system and the significance of reference points. Aligning on consistent usage enables more reliable estimates and simplifies Agile project planning and management. Don’t hesitate to explore these various approaches to find the one that best suits your team and project context.