You can estimate the effort which it will take to implement the story.
An effort estimate is given as both a 50% value (I am 50% sure that the story can be completed with this estimate) and a 90% value (I am 90% sure that the story can be completed with this estimate). Logically, the 90% value is always the largest.
The size of stories is estimated in story points (0, 0.5, 1, 2, 3, 5, 8, 13, 20, 40, 100).
Smaller stories can usually be estimated more precisely. Therefore the distance between available story points is smaller at the start of the range.
If the story is too big to be included in a sprint or too complex to be developed, then you should create it as an epic instead. Before implementation, the epic should be split into more smaller stories (created as children of the epic).
Value Estimate and Kano Type
Likewise, the value of the story can be estimated. First you have to access whether this story even has a value or if it is too small to have a value of its own. Then you evaluate its value type based on the Kano assessment.
If the story is a Must have, then there is no point in determining the value – it needs to be implemented no matter what (and the value is therefore automatically set to follow the effort estimate).
If the story on the other hand is an Exciter or a Satisfier, you can set the value estimate as a 50% and 90% number (I am 50% that the value is this high, but 90% sure that the value is at least this high) – the 90% number is logically the lowest.
If the story is of Kano type Indifferent or Reverse, then it obviously has no value.
Effort and Value Aggregation
Both the effort story points and the value estimations are summarized to the above level in the Storymap Tree. If no value has been entered, a default value (e.g. 5) is used in the calculation.