# How we measure impressions

How ATTEX measures ads and attention on mobile. Built on the IAB and MRC guidelines wherever they define a rule.

## Panel, screen and eyes

- **Panel:** recruited, consenting Android users in Sweden, Norway, Denmark and Finland.
- **Screen:** the ATTEX app records what is on screen each time it changes: every app and website, including feeds and in-app ads.
- **Eyes:** Tobii eye tracking through the front camera, calibrated per panelist.

## Definitions

Each definition names its source: the export column where ATTEX's own rule lands, and the industry guideline it follows, linked to the page.

| Term | Definition | Source |
|---|---|---|
| Ad | A paid placement, found by its ad label ("Annons", "Sponsrad", "Reklam", "Sponsored" …) or its ad-serving element. | [ATTEX · one ad is one row](/docs) |
| Impression | One continuous exposure of one ad on screen, counted when the ad appears. The industry rule counts an ad once it begins to render; ATTEX also requires it to be on screen. | [ATTEX · one impression is one row](/docs/data-dictionary#impression_id) · [IAB/MMA/MRC in-app guidelines, §3.1](https://www.iab.com/wp-content/uploads/2017/11/Mobile-In-App-Measurement-Guidelines-MMTF-Final-v1.1.pdf#page=8 "at minimum begins to render on the device") |
| Duration | From when the ad appears to when it leaves the screen: the device's next screen change after the ad was last recorded, in the same app or another, at most 60 seconds later and 10 minutes after the ad appeared, and earlier when the camera stopped. | [ATTEX · `duration_s`](/docs/data-dictionary#duration_s) |
| Fixation | The gaze resting on one point of the ad for at least 100 ms, counted only where the ad is at that moment. | [ATTEX · `is_fixated`](/docs/data-dictionary#is_fixated) · [IAB/MRC attention guidelines, p. 17](https://www.iab.com/wp-content/uploads/2025/11/IAB_MRC_Attention_Measurement_Guidelines_November_2025.pdf#page=17 "Fixations must be mapped to ad bounding boxes") · [Salvucci & Goldberg 2000](https://doi.org/10.1145/355017.355028 "fixations are rarely less than 100 ms") |
| Attention rate | Impressions with a fixation ÷ impressions with eye tracking. The base is the impressions where gaze was measured (`eyetracker_enabled`), with no viewability condition. | [ATTEX · `eyetracker_enabled`](/docs/data-dictionary#eyetracker_enabled) |
| Attention time | Fixation time on the ad per fixated impression. | [ATTEX · `fixation_duration_ms`](/docs/data-dictionary#fixation_duration_ms) |
| Advertiser | The party that paid for the ad, read from the ad itself: the sponsoring account, the landing domain or the advertised app. | [ATTEX · `brand`](/docs/data-dictionary#brand) |
| Industry | Each advertiser is assigned once to the most specific fitting category of the taxonomy, for example Vehicles > Electric Vehicles. The categories are IAB Tech Lab's; the one-category rule is ATTEX's. | [IAB Tech Lab Ad Product Taxonomy 2.0](https://iabtechlab.com/standards/ad-product-taxonomy/) |

In the export, an impression is one row. Duration is `duration_s`, from `first_seen` to `last_seen`; eye tracking is `eyetracker_enabled`; fixation is `fixation_duration_ms` and `is_fixated`; the advertiser is `brand` and the industry `industry_path`. [Data dictionary →](/docs/data-dictionary)

**Not measured yet:** image-only ads with no label, and video ads drawn inside a player.