What does confidence level mean in statistics?

What does confidence level mean in statistics?

A confidence level is a statistical measure that indicates the degree of certainty in a sample estimate. It reflects how confident we are that the true parameter lies within a specified range.

How is it calculated?

It's calculated using the sample mean, the standard deviation, and the size of the sample. The formula often involves the z-score or t-score depending on the sample size.

Can you give me an example?

Sure! If you have a sample mean of 50, a standard deviation of 10, and a sample size of 30, a 95% confidence level would mean the true mean is likely between 47.5 and 52.5.

What does a higher confidence level imply?

A higher confidence level implies a wider confidence interval, meaning you are more certain that the true parameter lies within that range, but it also means less precision.