Planning an experiment, clinical study, or survey? Enter your test type, significance level, expected effect size, and sample size to estimate power or work backward to a target sample size. Compare design options, such as two-sided versus one-sided tests, and see which assumptions drive the result. You leave with a power estimate, sample-size target, and stated assumptions for your analysis plan.
Statistical Power
Calculate statistical power and estimate the sample size your study needs.
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What it writes
- Required sample size per group
- Estimated statistical power
- Design assumption comparison
How to use it
Include the exact test, one- or two-sided hypothesis, alpha, target power, and expected effect size. For two groups, state whether the sample size is per group or total.
What you bring
- Planned test and study design
- Expected effect size or smallest effect
- Significance level and target power
- Choose a primary outcome and test
A good fit for
- Choosing a sample size before launching a controlled experiment
- Checking whether a completed study could detect its target effect
- Comparing power across planned study designs and effect sizes
Ways to start
A few requests this Agent can handle.
I’m comparing two independent groups with a two-sided t-test. What sample size per group gives 80% power for Cohen’s d = 0.5 at alpha 0.05?
My study has 40 participants per group, alpha 0.05, and an expected standardized effect of 0.4. Estimate power for a two-sided independent-groups t-test.
Compare power for 30, 45, and 60 participants per group in a two-sided test, assuming Cohen’s d = 0.35 and alpha 0.05.
Good to know
This workspace provides text assistance.
- Interpreting clinical importance from power alone
- Choosing an effect size without subject knowledge
- Estimates depend on the assumptions and numbers you enter
- Does not inspect datasets or run statistical software
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What am I buying?
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Checkout creates or uses your Ai-GEN account. When payment and entitlement are confirmed, the purchased Agent opens. Choose a starter task, add your inputs, and send your first request.
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Can I use the response in my work?
Use it as a draft to review and adapt. Verify calculations, facts, rights, and suitability before relying on it. Do not provide information you do not have permission to share.
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