Part 2 of 4 : When Proof Beats Proxy
How a travel advertiser cut cost per acquisition 6–7x with Consumer Purchase Audiences
By Luca Ledonne, Vice President, Agency and Platform Sales
In Part 1, we made the case for purchases as the optimal deterministic metric and predictive modeling as the key to understanding what consumers will do next. In Part 2, we prove it with a real-world case study and a clear playbook that shows how to apply the approach.
The Problem
Behavioral and keyword data tell you who is interested in a category, but they don’t reliably tell you who is acting, or who is poised to act next. That was a challenge a travel advertiser brought to Affinity Solutions: their existing keyword and behavioral campaigns were generating volume, but cost per acquisition was climbing, and efficiency was hard to defend. They were paying for everyone who looked like a traveler. They wanted to reach the ones who actually were — and those most likely to book next.
The fix wasn’t a new creative or a new bid strategy. It was a better signal, scored predictively.
Solution: Verified Travelers, Ranked by Likelihood to Convert
Affinity Solutions built a custom Consumer Purchase Audience of consumers who had made verified international travel purchases within the last 60 days, sourced directly from real transaction data, refreshed daily, and scored using advanced machine learning to prioritize the highest-propensity travelers.
Propensity Scores translated the consumer’s spend history into a forward-looking probability of conversion. There was no reliance on inferred “likely traveler” personas. Activation was driven by verified consumer travel spending, ranked by likelihood to convert next.
The Result: 6–7x Lower Cost Per Acquisition
In a direct head-to-head against Google’s keyword and behavioral segments, Affinity’s Consumer Purchase Audiences delivered a 6 to 7 times reduction in cost per acquisition.
Efficiency at that scale doesn’t come from reaching more people. It comes from upgrading the signal behind every impression. That’s where deterministic Consumer Purchase Insights and predictive scoring optimize outcomes.
Empower Your Campaign Strategies
Verified consumer purchase insights beat proxy metrics. Knowing what someone bought is fundamentally stronger than knowing what they searched for. Proof eliminates the guesswork that drives up the cost per acquisition.
Predictive scoring is the multiplier. Identifying recent buyers is half the story. Ranking them by likelihood to convert next is what turns a precise audience into a high-yield campaign.
Whether you’re looking for custom-built audiences based on specific parameters, syndicated segments you can activate today, or audiences built for the biggest seasonal moments, Affinity Solutions Consumer Purchase Audiences drive real outcomes.
Run This Play: The Audience Quality Reset
- When to run it: Intent-based channels (search, social, behavioral) are hitting diminishing returns, and cost per acquisition is climbing in a category with measurable transaction history like travel, retail, QSR, subscription services.
- What you need: A defined target purchase behavior and time window (e.g., “international travel, last 60 days”); Affinity Solutions’ Propensity Scoring layered on the audience to prioritize future purchase likelihood; a head-to-head test against your current channel to measure lift.
- What it delivered: 6–7x lower cost per acquisition versus Google keyword and behavioral targeting in head-to-head testing.
Up next — Part 3: One Source of Truth, Four Audiences.
