How do I choose the right sample size for my testing?

How do I choose the right sample size for my testing?

Choosing the right sample size is crucial for accurate results. It depends on factors like the population size, margin of error, and confidence level.

What factors should I consider when determining the sample size?

You should consider the population size, the expected effect size, the desired confidence level, and the margin of error.

Can you explain what margin of error means?

Margin of error indicates the range within which the true population parameter is expected to fall. A smaller margin of error requires a larger sample size.

Is there a formula I can use to calculate sample size?

Yes, a common formula is: n = (Z^2 * p * (1-p)) / E^2, where n is the sample size, Z is the Z-value, p is the estimated proportion, and E is the margin of error.