Plan power first
Sample-size planning happened before generating the simulated experiment data.
A simulated checkout A/B test where a positive aggregate result did not survive correction across multiple tests. The robust signal was on mobile, with a page-speed guardrail to monitor.
The analysis moves from test design to a scoped recommendation.
Define the test and the metric
Check the sample can detect the effect
Significance on each comparison
Adjust for multiple testing
Roll out to mobile, test desktop apart
A simulated e-commerce checkout redesign appeared to improve aggregate conversion with a raw p-value of 0.015. But the project evaluated ten significance tests. After Benjamini–Hochberg correction, the aggregate adjusted p-value was 0.050, while a mobile segment still showed a robust effect. The decision had to account for both statistical uncertainty and guardrail regressions.
The diagram shows how data moves through the project.
Python uses pandas, SciPy and statsmodels for analysis; DuckDB stores simulated sessions and orders. Power BI presents the resulting decision and guardrails.
Sample-size planning happened before generating the simulated experiment data.
Benjamini–Hochberg adjustment changed the interpretation of the aggregate result.
Refunds, tickets and page load time are assessed alongside conversion, with explicit device and user-type segmentation.
Scope and measurement matter as much as the headline numbers.
Relative conversion lift in the mobile segment; adjusted p=0.003.
Raw p=0.015, adjusted p=0.050 across the ten tests in this analysis.
The new flow significantly worsened page load time, p < 0.0001, and needs monitoring.
Projected impact: The analysis estimates approximately $857,401 in additional annual revenue for a mobile-only rollout. It is an assumption-based projection from a simulated experiment, not realized revenue. The recommendation is to roll out to mobile, test desktop separately, and monitor speed.
Multiple-testing correction turned a tempting headline win into a statistical near-miss. The analysis changed the recommendation rather than hiding the correction.
Page load time worsened under treatment; the decision report calls for monitoring instead of focusing only on conversion.
The mobile effect should not be applied to desktop. A separate desktop test is the next measurement step.
The repository includes analysis scripts, methodology documents, tests, a Power BI report and screenshots. The Power BI report is shared as screenshots and a .pbix file in the repository.