When you are in the middle of a design project, you may reach a point where you have to narrow down a set of ideas. It can be overwhelming to rank each idea against each other, and it is difficult to reason about a large number of concepts simultaneously to find a stand-out idea. In this scenario, using an affinity map can help you better understand the field of ideas you are working with.
What is an affinity map?
An affinity map is a tool that can be used to rank ideas or concepts against a set of criteria. It is laid out on a 2-dimensional space with two-axis that are each used for different criteria. Ideas are then placed on the affinity map relative to where they rank against the criteria, high or low on one axis and high or low on the other axis. This idea works well both physically and digitally as long as the ideas are moveable. We used digital sticky notes that could be easily slid around on the affinity map. After placing all of the ideas on the map one at a time, you can easily visualize which ideas fit your optimal criteria.
How did I use the affinity map?
Just before the prototyping phase, my team needed to settle on what we thought was our best idea to move forward with. We wanted an idea that was both impactful, and realistic to implement. Having so many ideas was both a blessing and a curse, this is a snapshot of what we were working with after the group brainstorm:
Knowing some of the criteria that we wanted in our prototype enabled us to use an affinity map. On one axis was “risk” and on the other axis was the “impact/reach”, both from low to high. We were able to drag all of the ideas onto this affinity map to see which had the potential to be the most rewarding. This process also made it easier to vote on the ideas because it gave us a heuristic to better understand the ideas within. The ideas we liked the most are in pink below, so you can see that these all fall into higher reward, and the idea that we settled on was in the quadrant of both low risk and high impact.
Although my team did use this method for group work, I think it is more suited for individual work. Because the criteria that were put on the axis were subjective, ideas that one person may have rated as very high risk might have only been rated as a moderate risk by another member. The ratings can be more consistent if they are done by a single person because even if the ratings are subjective, they can be consistently subjective.
Advantages
- Systematically ranks ideas against consistent criteria
- Clearly differentiates stand-out ideas
- Reduces the effort needed to reason about a large set of data/ideas
Disadvantages
- Subjective rankings are not conducive to teamwork
- Idea generation must take place beforehand
- Can only be used on two criteria (axis) at a time
Affinity mapping can be used to trim down a set of ideas after the creation of the ideas. It can show which of the concepts you are working with has the highest affinity to a certain set of criteria. It can provide another lens to help you better understand the set of concepts you are working with.