Guide to Measuring Incrementality: Towards a More Structured Approach in Retail Media

Retail Media now accounts for 11% of total advertising spend in France (source: SRI, 2024), confirming its strategic role in the media strategies of both brands and retailers. However, measuring its performance remains a major challenge—both technically and methodologically.

Incrementality: A Key Yet Underused Performance Indicator

Among the key metrics, incrementality measurement is essential for assessing the real effectiveness of campaigns. Yet, the concept is often vague, poorly understood, and difficult to implement consistently.

A Guide to Better Understand and Activate Incrementality Measurement

In light of these challenges, Alliance Digitale is publishing a Guide to Measuring Incrementality to help Retail Media professionals—brands, agencies, sales houses, and AdTech players—understand and apply the various available evaluation methods.

This guide was developed by the Retail Media Commission's Measurement Working Group, with support from the Retailers Working Group.

Four Objectives to Structure Retail Media Measurement

The Guide to Measuring Incrementality is built around four main objectives:

1. Clarify existing methodologies
2. Help stakeholders choose the most suitable approach based on business objectives
3. Encourage a strategic approach to measurement
4. Promote a shared language across the ecosystem

Three Main Families of Measurement Methods

The guide identifies and compares three core families of incrementality measurement methods:

• Simple comparisons: by time period, geography, or exposure level
• A/B tests: using control and exposed groups in controlled environments
• Statistical modelling: including Marketing Mix Modeling (MMM) and counterfactual approaches

Each method is illustrated through real-world case studies, outlining conditions for implementation, key strengths, and limitations.

Three Levels of Understanding for All Profiles

The guide is structured to accommodate various levels of expertise:

• Level 1 – Introduction: fundamentals of incrementality measurement
• Level 2 – Intermediate: applying methods in operational contexts
• Level 3 – Expert: mastering advanced models and complex systems

A Tool to Professionalize Retail Media in France

Through this publication, Alliance Digitale reaffirms its commitment to the professionalization and structuring of the Retail Media ecosystem in France. The objective is to foster a shared understanding of campaign performance, based on rigorous, comparable, and actionable measurement methods.

Download the guide and take action
The Guide to Measuring Incrementality is now available on the Alliance Digitale website or below.