mike cohn - background...planning poker for estimating •an iterative approach to estimating...

Planning and Trackingon Agile Projects

Mike Cohn - background

© Mountain Goat Software, LLC

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Wednesday, August 23, 2006

Copyright Mountain Goat Software, LLC

Imagine...

• That you’re fed up with software development as a career

• And you decide to go into the landscaping business

• Your first job is moving this pile of rock from the front of my house to the back


How might you estimate this?• One way:

• Look at the pile of rock and estimate how many wheelbarrow loads it represents

• After an hour, see how many wheelbarrow loads you’ve moved then extrapolate the total duration

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My landscaping

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Noon 1pm 2pm 3pm 4pm 5pm

Wheelb

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Loads


Release, iteration, & velocity

•A release comprises multiple iterations

•Each iteration can be thought of as a same-sized box

•Stories are put into each box until it’s full

•The size of the box is the planned velocity

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The planning onion


Relating the different planning levels

As a frequent flyer, I want to...





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Itera

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Itera

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Product Backlog Iteration Backlog

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An agile approach to planning

Feedback

Feedback


Estimating

Release planning

Burndown charts

Task boards

Agenda

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Story points

• The most common way for agile teams to estimate these days is in “Story Points”

• Based on a combination of the size and complexity of the work

• Unitless but numerically relevant estimates

• A 10-point story is expected to take twice as long as a 5-point story


Consider these two piles of work

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Dog points

Assign “dog

points” to the

following breeds


Two key advantages

• Estimating in story points

1. Forces the use of relative estimating

• Studies have shown we’re better at this

2. Focuses us on estimating the size, not the duration

• We derive duration empirically by seeing how much we complete per iteration

3. Puts estimates in units that we can add together

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Planning poker for estimating

• An iterative approach to estimating

• Steps

• Each estimator is given a deck of cards, each card has a valid estimate written on it

• Customer/Product owner reads a story and it’s discussed briefly

• Each estimator selects a card that’s his or her estimate

• Cards are turned over so all can see them

• Discuss differences (especially outliers)

• Re-estimate until estimates converge


Planning poker - an example

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Why planning poker works

• Emphasizes relative estimating

• Focuses most estimates within an approximate one order of magnitude

• Everyone’s opinion is heard

• Estimators are required to justify estimates

• Estimates are constrained to a set of values

• It’s quick and fun


Estimating

Release planning

Burndown charts

Task boards

Agenda

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An agile release plan

We’ll be here by the planned deadline

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ackl

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Look at velocity in a few ways

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Velocity

Iterations

Mean (Worst 3) = 28

Mean (Last 8) = 33Last Observation = 36

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Extrapolate from velocity

At current velocity we’ll finish here

At our slowest velocity we’ll finish here

At our long-term average we’ll finish here


Estimating

Release planning

Burndown charts

Task boards

Agenda

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How’s my landscaping coming?

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Noon 1pm 2pm 3pm 4pm 5pm

Wheelb

arr

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Loads


Remember the different levels?






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Itera

tion 2

Itera

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Product Backlog Iteration Backlog

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An iteration burndown chart

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Hours


When will this project be released?

Sto

ry P

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Sprints

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Estimating

Release planning

Burndown charts

Task boards

Agenda


Task boardsStory To Do

InProcess

ToVerify Done

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A sample task board


A cork task board

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A hanging tack board


Velcro in a team room

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Repurposing the cabinets


Mike Cohn contact info

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mike cohn - background...planning poker for estimating •an iterative approach to estimating...

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