Extension by SegmentStream

Incrementality Testing

Geo holdout experiments that measure what a channel adds on top of what would have happened anyway. Built on SegmentStream's GeoLift work.

Start a pilot Join the waitlist

What it adds to your workspace

Market selection in three phases, with A/A validation
Synthetic control groups for each test
Incremental lift and confidence, written up when the test ends

Works with

Conversions by region

Install

$ segmentstream add incrementality-testing

▸ files added to your workspace repo

▸ deploy to start

Or ask your agent

“Plan a geo holdout test for our YouTube spend.”

Pricing

Included during early access. Runs on platform usage.

How it works

What this model measures, how it works, and where it can be wrong.

Incrementality TestingGeo holdout experiments with synthetic control groups that measure what your ads actually add — not what attribution claims they do.6 min read

Part of these solutions

Marketing analytics

Attribution and budget optimization on first-party data

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Attribution that cross-validates, reported at click time.

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Predictive Attribution

Projected ROAS within days, for conversions still on their way.

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Browse the marketplace →

Enterprise pilot

Want Incrementality Testing set up for you?

Our forward-deployed engineers build one solution on your data, in your own workspace, as code you own. Tell us what you run today and what you want; your note goes straight to our founder.

One solution, on your data, in your own workspace
First version live in two weeks
Parity proven before anything is switched off
Fixed scope and price, credited to your contract if you continue

Not ready for a pilot? Send the form anyway with your question. An engineer will reply, not a sales rep.

How the pilot works

Your company’s context, ready for every agent.

$ segmentstream workspace create acme --region eu

▸ workspace ready · data, objects, metrics and access rules in one place

▸ connect Claude, ChatGPT or Cursor with one connector

▸ tell your agent: “add our billing API as a source”

Start a pilot

Our engineers build the first version on your data in two weeks, at a fixed price.

Or join the waitlist for self-serve:

Pilots are open now. Self-serve opens to the waitlist this fall.