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📊 Stratification in CUPED
2/18/2026
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📊 Stratification in CUPED
We’ve enhanced our CUPED variance reduction methodology in Cloud by automatically applying Stratification to better account for users with missing pre-experiment data.
How it Works
Users are grouped into strata based on available pre-experiment information. Treatment effects are then calculated within each group before being aggregated into a single estimate and applying standard difference-in-means and variance calculations.
Impact on your Analysis
This improvement retains more users in analysis while still applying variance reduction wherever pre-experiment data exists. The result is tighter confidence intervals for more reliable decision-making.
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"Statsig's experimentation capabilities stand apart from other platforms we've evaluated. The ease of use, simplicity of integration help us efficiently get insight from every experiment we run. Statsig's infrastructure and experimentation workflows have also been crucial in helping us scale to hundreds of experiments across hundreds of millions of users."
Paul Ellwood
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Rami Khalaf
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Shannon Priem
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Partha Sarathi
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Jeff To
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Matteo Hertel
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Preethi Ramani
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Berengere Pohr
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Brooks Taylor
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Ahmed Muneeb
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Karandeep Anand
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"We only had so many analysts. Statsig provided the necessary tools to remove the bottleneck. I know that we are able to impact our key business metrics in a positive way with Statsig. We are definitely heading in the right direction with Statsig."
Partha Sarathi
Director of Engineering
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Joel Witten
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Omar Guenena
Engineering Manager
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Michael Sheldon
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Elaine Tiburske
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Paul Frazee
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Alessio Maffeis
Engineering Manager
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Toney Wen
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Michael Koch
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Mengying Li
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Dave Cummings
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Andy Glover
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Laura Spencer
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Evelina Achilli
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Jared Bauman
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Laura Spencer
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Duncan Wang
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Todd Rudak
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Rafael Blay
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