Question 1

What is a confidence interval?

Accepted Answer

A confidence interval is a range of values that likely contains the true population parameter. A 95% CI means if you repeated the experiment many times, 95% of the intervals would contain the true value.

Question 2

What does 95% confidence mean?

Accepted Answer

It means you can be 95% confident the true value falls within the interval. It does not mean there's a 95% probability the parameter is in this specific interval.

Question 3

How do I interpret overlapping confidence intervals?

Accepted Answer

Overlapping CIs don't necessarily mean no significant difference. For precise comparison, look at the CI of the difference between groups, or perform a statistical test.

Question 4

Why are my confidence intervals so wide?

Accepted Answer

Wide intervals result from small sample sizes or high variability. Increase your sample size or reduce measurement noise to get narrower, more precise intervals.

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