We have found it useful to size stories based on their relative complexity. More complex stories will take more effort to complete. Feature complexity typically relates to the degree of interconnectedness of a feature. This can be its own inter-connectedness or the number of connections to other features. Interestingly enough, it takes about the same number of words to describe a simple story as it does to describe a complex story.
Challenges in estimation
Some of the biggest challenges we have in estimation include:
We have to remember that estimates are really just our best guesses of the effort required based on our current information. We’ll have more information later and will refine our estimate then, and as we go along.
We have found it easier to make estimates based on a value relative to another estimate. In other words, it is easier, and more accurate, to say “feature A will take twice the effort feature B will” than it is to estimate features A and B separately. A simple way to do relative estimation is with a game called “Team Estimation” created by Steve Bockman.
Team estimation game play
The “rules” for team estimation are very simple:
Throughout this time, anyone is free to invoke others in conversation about why they are moving cards and what they think about the size of the stories. Remember, however, that we are just making estimates, so conversations to help clarify what the stories are is useful, but getting too hung up on the exact size of the estimates is not worthwhile.
The following diagrams illustrate how the story cards are arranged on the table. Figure 1 shows how the cards are laid out at the beginning.
After a few cards have been played, the story cards might look like those shown in Figure 2:
At this point, possible plays would be to:
When you move a story to another column you are basically saying “this story has been misestimated.” For example, figure 3 shows a possible play of a card (moving the card from one column to another). In this case, it means that don’t think the card being moved is significantly larger than the stories in the leftmost column.
Finally, we get to the point shown below:
At this time, the number of story points for each column can be assigned. These should be based on what you consider to be allowable story points. We like using the sequence:
0, 1, 2, 3, 5, 8, 13, 20, 40, 100, 200, 400, 800
Figure 5 shows labeling the columns with the estimated story point sizes.
After these are agreed upon, these story point sizes should be written on each card.
Team Estimation for MBIs and features
While we have described Team Estimation for stories, it should be clear we could use it just as well for MBIs and features.
Advantages of Team Estimation over Planning Poker
Faster and more fun
Prior to learning about Team Estimation, we had used a technique called Planning Poker. We have
When not everyone can estimate the entire item
Planning poker requires that everyone can estimate all of the items. In reality, however, two variations sometimes occur:
Part of the advantage of Team Estimation is that it works better than Planning Poker when team