Estimating effort
Traditionally, absolute duration measures, such as person-hours, are used to estimate tasks. Agile approaches generally apply relative measures, especially for large work items such as epics, use cases, and larger user stories. When estimating smaller work items of a duration of a few hours, it is still common to use person hours. The reasoning is that it is difficult to accurately estimate weeks- or months-duration work items, but there is better accuracy in estimating small work items of 1-4 hours.
There are a number of means by which effort can be estimated, but the one we will discuss in this recipe is called planning poker. This is a cooperative game-like approach to converge on a relative duration measure for a set of work items.
Purpose
The purpose of effort estimation is to understand the amount of effort required to complete a work item. This may be expressed in absolute or relative terms, with relative terms preferred for larger work items.
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