Google has released Meridian GeoX globally, giving advertisers a way to test whether their spending generates extra sales or gets credit for purchases that would have happened anyway.
The open-source tool helps businesses run advertising experiments across different geographic areas. It can measure campaigns across advertising platforms, including those outside Google, and assess both online and offline sales. Google announced the global release after introducing the product earlier this year.
Google used the launch to criticize how advertising performance is often reported.
“Click-based attribution tools consistently double-count conversions,” the company wrote, warning that businesses can end up with “green dashboards, but flat bottom lines.”
Consider a shopper who clicks a social media ad, later clicks a search ad and then buys a product. Depending on how the reporting is configured, both platforms might claim the purchase. The business still made one sale. And even counting that sale correctly does not establish whether the customer needed either ad to make the purchase.
GeoX is designed to investigate that second problem. Marketers call it incrementality: the extra business an advertisement actually causes.
For example, a retailer could pause a campaign in selected regions while keeping it running in others. GeoX uses historical data and results from the experiment to estimate the effect of that change. The aim is to work out how sales differed from what would have been expected without the intervention. Google’s experiment guide describes the process, from collecting regional data to evaluating whether the measured effect is statistically significant.
Advertisers can also increase spending in selected areas to test whether a larger budget brings in additional business. The software supports testing several changes against a shared comparison group, which Google says can reduce the cost and time needed to run experiments. Google’s product documentation outlines the available designs.
Results can be used independently or fed into Meridian, Google’s existing marketing measurement software, to refine estimates of advertising returns and help businesses decide where to allocate their budgets. Because GeoX is open source, teams can inspect its code and methods.
Using it requires preparation. Advertisers need historical daily sales or other performance data broken down by geography, plus spending data for experiments that change existing campaign budgets. They also have to implement the campaign changes and collect results during the test.
Google’s technical paper identifies differences between regions and changing patterns over time as obstacles to reliable measurement. The researchers say GeoX’s methods improve accuracy and reduce experiment costs in their benchmarks.
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