E S T I M A T E S

F I L I P E L O U R O ( S C R U M M A S T E R / A G I L E C O A C H )

“ E S T I M A T I O N I S T H E P R O C E S S O F F I N D I N G A N

A P P R O X I M A T I O N O F A V A L U E T H A T W I L L B E U S E D F O R

S O M E P U R P O S E ”

F R O M W I K I P E D I A

W E A T H E R F O R E C A S T SL E S S O N S L E A R N E D ( P A R A G L I D I N G )

E X E R C I S E

• Project

- 2 months for Design and Architecture

- 4 months for Development

- 1 month for Testing

• Scenario

- Design and Architecture Estimate is Wrong by 2 weeks

- What will you do?

• Solutions

- Force the Developers to Work Harder?

- Delay the Project By 2 Weeks?

- Delay the Project By 25% (Best Alternative)

S T A T I S T I C S

( 5 0 Y E A R S )

• The first estimate at the

beginning of a project can be

wrong by a +/- 4x factor

• Lack of Details

• Complexity

• To deal with this we spend a lot

of time on the requirements /

design / architecture.

• As more detail are added our

Estimates get better

T H E C O N E O F U N C E R T A I N T Y

S T A T I S T I C S

E S T I M A T E S A R E I N A C C U R A T E

E S T I M A T E S

A G I L E E S T I M A T I O N

• Agile Estimation embraces the cone of uncertainty!

• Deviations become “More Accurate Estimations”.

• The estimates are revised every sprint or iteration.