Filter Exposures

You can use Qualifying Events to filter exposures to units who did or did not trigger an event after being exposed. This is a powerful tool, especially for analysis-only experiments where the assignment tool may have over-exposed units (e.g. assigning units on page load when the intervention was only triggered when a button was clicked).

We recommend caution using this tool, as it's possible to introduce post-assignment data into your assignment data, biasing results.

There are a few settings:

• Qualifying Event: the event source to qualify exposures with. This can be filtered, so you can pick specific target events within a qualifying event source
• Exclude matching units: whether to include, or exclude units who triggered the event
• Use qualifying event timestamp for first exposures: if the actual intervention occurred when the unit triggered the qualifying event, check this so that Statsig knows to override the exposure timestamp with the qualifying event timestamp
• Filter events by time window: restrict the qualifying event matching to events that happened within X days/minutes of the unit's exposure event