Step by stepLet me walk through how I do it.
- We have a product backlog. Usually user stories.
- We identify the right people to be the business value experts. We recommend that they participated in developing the PB. Typically 5 people. I call them the business stakeholders (maybe not what your company means by that word...just the key people to do this and participate in the Sprint Review) and the Product Owner. The 5 best experts. (Sometimes you have 4 people or 6 people.)
- We discuss BV drivers. To make the concept of 'business value' more concrete in this specific situation.
- We choose the highest BV card. We give it 100 BVPs (BV points). It becomes the reference story for BV.
- We select cards randomly. And compare them to the reference story. The experts vote on BV using the Fibonacci cards. I recommend the full true Fibonacci series up to 144. If you want to add some cards at the high end (some, not many), I think it will not hurt.
- They discuss and then 'secretly' vote. 1-2-3 show. Everyone shows his poker card. If the cards are all with 3 Fibonacci numbers of each other (eg, 21-34-55), then sum the cards and average to the nearest integer.
- If they are not close, then discuss (especially the highest and lowest voters), enough so that the 5 voters learn something. Then re-vote.
- On average, allow about 1 minute per card. Maybe slightly more. They will discuss the first few cards more slowly than that, and the last half of the story cards will go more quickly, on average. Do not let them get take more then 75 minutes for 50 use stories. Go fairly quickly.
- When you are done as a team, then arrange the cards of similar BVPs. And you ask the experts...do you see any cards that now look 'out of kilter?' Often they will identify a few user stories to be re-voted. And then they do that.