Written by the Fiveable Content Team โข Last updated September 2025
Written by the Fiveable Content Team โข Last updated September 2025
Definition
Confidence level represents the percentage of all possible samples that can be expected to include the true population parameter. It indicates the degree of certainty associated with a confidence interval.
5 Must Know Facts For Your Next Test
The most common confidence levels are 90%, 95%, and 99%.
A higher confidence level means a wider confidence interval.
Confidence level is denoted by (1 - ฮฑ), where ฮฑ is the significance level.
Increasing sample size can reduce the margin of error while maintaining the same confidence level.
The critical value corresponding to a given confidence level can be found using the standard normal distribution.