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An A/B test compares a $10\%$ baseline conversion with a hoped-for $11\%$ . At a two-sided $5\%$ level and $80\%$ power, roughly how many users per arm are needed?

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Experiment design: randomisation, peeking and minimum detectable effect

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Citadel, Two Sigma

An A/B test compares a 10%10\%10% baseline conversion with a hoped-for 11%11\%11%. At a two-sided 5%5\%5% level and 80%80\%80% power, roughly how many users per arm are needed?

More statistics and inference questions

An A/B test compares a $10\%$ baseline conversion with a hoped-for $11\%$ . At a two-sided $5\%$ level and $80\%$ power, roughly how many users per arm are needed?