> For the complete documentation index, see [llms.txt](https://upgrade-platform.gitbook.io/upgrade-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://upgrade-platform.gitbook.io/upgrade-documentation/creating-an-experiment/unit-of-assignment.md).

# Unit of Assignment

## Individual Assignment

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When selecting individual assignment, each included participant will be randomly assigned a condition.

## Group Assignment

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Group assignment references one or more of the group types that have been previously defined in the [Context Metadata](/upgrade-documentation/developer-guide/reference/context-metadata.md). For the selected group type, each group will be randomly assigned a condition, and each participant in a group will receive the same condition as the rest of the group.

## Within-Subjects Assignment

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In within-subjects assignment, every time a participant visits a decision point (and `/markExperimentPoint` is called), the participant is eligible to receive a new condition. There are different options for determining the order of such conditions for within-subjects experiments. Random will randomly select a condition each time the decision point has been marked. Random Round Robin will randomly order the experiment conditions, and when it runs out of conditions, will create a new random ordering. Ordered Round Robin will deliver the same sequence of conditions over and over again.