Many of the agile teams I know are using some form of planning poker for their agile estimation. Agile estimations with planning poker is sometimes just not working. Reasons for this can be: the estimation features are too large, the team is not inspired to poker 300 stories, there is not enough detailed information available on the items to be estimated or there is not enough time to do an accurate estimation on the full backlog.
The main principles behind agile estimation are: use a relative estimation, allow discussion to derive more information about the items, create mutual understanding and respect about the solutions, create team commitment on the work agreed upon and strengthen team relationship by collaborating. All estimations are done in relative units….. usually story points .
Here are 7 agile estimation techniques beyond Planning Poker.
1. Planning Poker
All participants use numbered playing cards and estimate the items. Voting is done anonymous and discussion is raised when there are large differences. Voting is repeated till the whole team reached consensus about the accurate estimation. Planning poker works well when you have to estimate a relative small number of items (max 10) in a small team (5-8 people). Tip: try to keep the voting between affordable numbers. Maximize the highest card to 13 points. More on planning poker via this link.
2. T-Shirt Sizes
This is a perfect technique for estimating a large backlog of relative large items. Especially when you have several concurrent scrum teams working on the same product. Items are estimated into t-shirt sizes: XS, S, M, L, XL. The decision about the size is based on an open and mutual collaborative discussion. This method is an informal and quick way to get an rough feeling about the total size of your backlog. More about T-shirt size estimation is here.
3. Dot Voting
When you are faced with a relative small set of items and in need of a super simple and effective technique to estimate you can use Dot Voting. This method has originated form decision making and you can use it for estimating. Each person gets a small number of small stickers and can choose to vote for the individual items. The more dots is an indicator of a bigger size. Works well in both small and large group. You have to limit the number of estimated items. More on dot voting here.
4. The Bucket System
Much faster than planning poker is the Bucket System. This system is a good alternative when estimating a large number of items with a large group of participants. Create several buckets in the sequence of planning poker. The group estimates the items by placing them in these “buckets”. Buckets are usually different sheets of brown paper where you can place the sticky note with the item. But you can also use actual baskets to limit discussion about already processed items. More on the bucket method here.
A very fast method of rough estimating is the Large/Uncertain/Small method. The team is being asked to place the items in one of these categories. The first step is to categorize the obvious items in the two extreme categories. Next the group can discuss the more complex items. This is actually a simplification of the bucket system. The system is especially good to use in smaller groups with comparable items. Next you can assign sizes to these 3 categories.
6. Affinity Mapping
This method is based on finding similarities in the estimated items. The team is asked to group them together. Best way is to execute this is a visual way and order them form small groups to large. It works best with a small group of people and a relative small number of items. You can assign estimation numbers to the different groups. More information about Affinity Mapping.
7. Ordering method
This is an exercise where you get an accurate image on the relative size of items. This works best in a small group of expert. All items are placed in random order on a scale label ranging from low to high. Every participant is being asked to move one item on the scale. Each move is just one spot lower or one spot higher or pass the turn. This continues till no team member want to move items and passes their turn. The ordering protocol is a method of getting fine grained size estimates. Works best with a relative small group of people and a large number of items.
These are different methods you can use to make agile estimation more efficient and an inspiring team effort. Please share your experiences with this below in the comments section.