Planning Poker for Estimating on Agile Projects

• What is Planning Poker?

  Planning Poker is a consensus-based approach to agile estimating. To start an estimating session, the product owner or customer reads a user story or describes a feature to the estimators, who should include everyone on the team. Each estimator is holding a deck of cards with values like 0, 1, 2, 3, 5, 8, 13, 20, 40, and 100, which is the sequence we recommend. The values represent the number of story points, ideal days, or other unit in which the team estimates.

  The estimators discuss the feature, asking questions of the product owner as needed. When the feature has been fully discussed, each estimator privately selects one card to represent their estimate. All cards are then revealed at the same time. If all estimators selected the same value, that becomes the estimate. If not, the estimators discuss their estimates. The high and low estimators should especially share their reasons. After further discussion, each estimator reselects an estimate card and all cards are again revealed at the same time.

  The process is repeated until consensus is achieved or until the estimators decide that estimating of a particular item needs to be deferred until additional information can be acquired.

• How can I get Planning Poker cards?

  Planning Poker cards are available in the Mountain Goat Software store. Two styles are available and we ship anywhere in the world. Mountain Goat Software’s branded cards are sold at cost as a courtesy to the agile community. Our full-color cards are the absolute highest-quality cards available anywhere. They are manufactured by the same company that prints many of the world’s most popular playing card brands, including Bicycle, Bee, and the World Poker Tour.

  We also offer royalty-free licenses to organizations that wish to produce their own cards. Contact us if you are interested in printing your own cards.

• When should we play?

  Most teams will hold a Planning Poker session shortly after an initial product backlog is written. This session (which may be spread over multiple days) is used to create initial estimates useful in scoping or sizing the project.

  Because product backlog items (usually in the form of user stories) will continue to be added through out the project, most teams will find it helpful to conduct subsequent estimating sessions once per iteration. Usually this is done a few days before the end of the iteration and immediately following a daily standup since the whole team is together at that time anyway.

• How can I do this with a distributed team?

  Simple—use the PlanningPoker.com website. We developed that website and offer it as a free service to the agile community. A product owner, ScrumMaster, or agile coach can log in and preload a set of items to be estimated. A private URL can then be shared with estimators who log in and join a conference call or Skype session. Estimating then proceeds as it would in person.

• Does Planning Poker work?

  Absolutely. Teams estimating with Planning Poker consistently report that they arrive at more accurate estimates than with any technique they’d used before.

  One reason Planning Poker leads to better estimates is because it brings together multiple expert opinions. Because these experts form a cross-functional team from all disciplines on a software project, they are better suited to the estimation task than anyone else. After completing a thorough review of the literature on software estimation, Magne Jørgensen, Ph.D., of the Simula Research Lab concluded that “the people most competent in solving the task should estimate it.

  Second, a lively dialogue ensues during Planning Poker and estimators are called upon by their peers to justify their estimates. Researchers have found that this improves estimate accuracy, especially on items with a lot of uncertainty as we find on most software projects.

  Further, being asked to justify estimates has also been shown to result in estimates that better compensate for missing information. This is important on an agile project because the user stories being estimated are often intentionally vague.

  Additionally, studies have shown that averaging individual estimates leads to better results as do group discussions of estimates.

• Where can I get Planning Poker cards?

  Mountain Goat Software sells Planning Poker cards through our online store.