Title: 10 Things to know about Confidence Intervals – MeasuringU
Headings: 10 Things to know about Confidence Intervals
10 Things to know about Confidence Intervals
Content: Three things impact the width of a confidence interval
Confidence level: This is the 95% part of the 95% confidence interval and also typically takes values of 90%, 99%, 80% and 85%. Confidence levels are the “advertised coverage” of a confidence interval. If we were to sample from the same user population 100 times, we’d expect the average to fall within the interval 95, 90 etc., times out of 100. Variability: as measured by the standard deviation. Populations (and samples) with more variability generate wider confidence intervals. Sample Size: Smaller sample sizes generate wider intervals.