Measurement Foundations: Audience Composition & Indexing

Understanding Audience Composition

Composition expresses the percent of a unit's impressions that are made up of a particular audience.

Think of it as a pie chart with slices representing mutually exclusive audiences. It can be based on any demographic profile available in the Geopath database. 

Calculating Percent Audience Composition

Why should I care about Audience Composition?

The value of more targeted units cannot be expressed by simply comparing the number of raw impressions, as impressions are a measure of quantity rather than quality.

Using high composition locations in a package allows us to consider a group of units with smaller impressions but with a higher concentration of the preferred target. These types of locations have a high-quality value for advertisers as there is a much higher likelihood of the advertiser's message getting in front of the right audience.

Creating and  Using an Index

While percent composition is a great tool to show how targeted a location or campaign is, without putting that number into perspective, you may thing that you need to find locations with very high composition percentages. Indices are an easy statistic used for comparison purposes and provide context.

To calculate a composition index, take the % composition and divide it by the % Target Population. Indices above 100 mean that the target is better represented. The inverse is also true. Indices below 100 tell us that the target is under-represented.

THINGS TO REMEMBER:

• Composition is the percent of a location's impressions against a defined audience, and provides a measure of audience concentration. The more narrowly defined the audience, the more helpful composition can be.
• While composition provides an additional audience metric to evaluate the suitability of locations, indexing puts that number into perspective.

If you have any questions or comments, please reach out to geekout@geopath.org!