Most of our text reading regarding confidence intervals focuses on deriving and calculating their values under a variety of circ
umstances. More important than that, though, is what we can do with confidence intervals as engineers. Discuss how knowing the confidence interval for some statistical parameter (typically, but not always, the mean value) can affect the decision-making we conduct around that parameter on engineering projects. What might we do differently as a result of having confidence in a range of values rather than feeling we actually know a specific value
As a general rule of thumb, a small confidence interval is better. The confidence interval will narrow as your sample size increases, which is why a larger sample is always preferred. As our page on sampling and sample design explains, your ideal experiment would involve the whole population, but this is not usually possible.
