What exactly is a confidence interval Please explain What ex

Solution

A confidence interval gives an estimated range of values which is likely to include an unknown population parameter, the estimated range being calculated from a given set of sample data.A confidence interval calculated for a measure of treatment effect shows the range within which the true treatment effect is likely to lie

Confidence intervals provide different information from that arising from hypothesis tests.

It is conventional to create confidence intervals at the 95% level – so this means that 95% of the time properly constructed confidence intervals should contain the true value of the variable of interest.

An increase in sample size will decrease the length of the confidence interval without reducing the level of confidence. This is because the standard deviation decreases as n increases