---
title: "Glossary of IAB Metrics"
slug: "glossary-of-iab-metrics"
description: "Explore IAB Standard metrics like auto-refresh events, distinct page views, and sessions to understand web traffic and user engagement effectively."
tags: ["Glossary", "IAB Reporting", "Measurement"]
updated: 2025-12-15T23:54:13Z
published: 2025-12-15T23:54:13Z
canonical: "help.quantcast.com/glossary-of-iab-metrics"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.quantcast.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Glossary of IAB Metrics

## Definitions of the Metrics

Below are the definitions of the IAB Standard metrics for a given property and publisher:

### Auto-refresh Events

The fraction of all events that appear to be triggered by an auto-refresh mechanism. We base our estimate on a frequency analysis of the publisher’s traffic, in which the regularity of auto-refreshed pages stands out from the background of human-requested pages.

### Auto-refresh Interval

The number of seconds between refreshes of the fastest auto-refreshing content discovered.

### Distinct Page Views

The number of full, human-requested web pages for which this publisher supplied some or all of the content. This is calculated from the raw HTML event count. We observed fewer correction factors for non-human traffic, multiple impressions, and auto-refresh.Events received

We received the number of pixel requests by counting all rows in our server logs.

### Multi-events

The fraction of all events that appear to be duplicates–that is, followed within one second by another event from the same user visiting the same publisher. Common reasons include fast redirects (sending the user to a second page as soon as the first has loaded), multiple tagged iframes, or multiple media types being tracked. A Quantified ad network serving ads across multiple iframes on a single page will typically generate multiple pixel requests within a second, which would be counted as multiple events. Similarly, a publisher using separate tags to track pages and the ad placements on those pages will see a significant increase in multi-event counts.

### Robot Events

The fraction of all events we estimate to be generated by non-human activity. In addition to the IAB’s bot and spider list, we use our own proprietary techniques to identify non-human activity.

### Sessions

The number of distinct visits of users to the property. Per the IAB's standard, a session is any period of activity (which could be a single page view or a multi-day marathon) separated by at least a half-hour of inactivity.Video plays

The number of post-buffering Flash video play events observed.

### Unique Cookies

The number of distinct Quantcast cookies we received with pixel requests.