2. Estimation
• The primary reason for estimating product
backlog items is so that predictions can be
made about how much functionality can be
delivered by what date
3. Estimation
• A typical way to estimate effort is in Hrs, Days
• But it has issues
– Provides a false sense of precision
– Doesn’t take into account uncertainty
– Introduces waste in Estimation process
– No apparent baseline
– Can’t really be used for forward projection based
on previous data (e.g. Velocity)
– Humans are not good at estimating in hrs
– Estimates are done by someone else rather than
those who will implement the task
4. Estimation – Story Points
• Abstract measure taking into account the
effort needed to complete a task.
• Effort involved can be influenced by risk,
uncertainty and complexity
• Allows team members with different skill
levels to communicate about and agree on an
estimate
• Provides a standard – due to relativity
5. Estimation – Planning Poker
• Establish a common baseline for use, typically 2 values which can be used
for triangulation
• Each team member has a deck of planning poker cards
• Each card has a number on it, representing an estimate e.g.
0,1/2,1,2,3,5,8,13,20,40,100,infinity
• As the story is presented, each member then picks up a card privately
from the deck to represent the estimate. All the members reveal their
estimates at the same time.
• There will be some discrepancy on these estimates selected by members
and that’s okay.
• Members with highest and lowest estimates explain their thoughts about
their selections resulting in possible discussions with other team members
• After the discussion the another round takes place for the same story.
• If the estimates selected by all the team members are more or less similar
then the estimate is selected, otherwise the process continues till there is
a consensus on the estimate for that user story.
Waste: As we do not necessarily have the complete details for the task / story how can we be precise about how long it will take us to complete the task?