n AAS sem reposição
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
This calculator helps determine the appropriate size for a simple random sample without replacement. It uses the finite population adjustment formula: n = n₀ / (1 + n₀/N), where n₀ is the initial sample size and N is the total population size. This is crucial when the sample constitutes a significant portion of the population, improving accuracy in statistical studies.
The formula accounts for the fact that, in sampling without replacement, each selected element cannot be chosen again. This reduces variability and adjusts the sample size to prevent overestimation in smaller populations. It's commonly used in market research, elections, or any scenario where the sample directly impacts the remaining population.
Use this tool when you already have an n₀ calculated (as in infinite populations) and need to adjust it considering the actual population size. Ensure N is known and the sample represents less than 5% of the population for the adjustment to be meaningful. The calculator streamlines manual calculations and avoids common descriptive statistics errors.
Frequently asked questions
Why use this formula instead of n₀?
This formula adjusts the sample size for finite populations, preventing overestimation when the sample represents a significant portion of the total population.
When should I use this calculator?
Use it when you have an already calculated n₀ and need to adjust the sample size considering the actual population size (N).
What's the difference between with and without replacement sampling?
Without replacement, each selected element can't be chosen again, directly affecting the sample size and calculation accuracy.
What if N is unknown?
The formula doesn't apply. Use methods for infinite populations or estimate N based on historical data.
How does the population size (N) affect results?
The larger N is relative to n₀, the smaller the adjustment impact. For very small N, this adjustment is critical.