Question

What do confidence intervals represent? What is the most controllable method of increasing the precision of or narrowing the confidence interval? What percentage of times will the mean, or population proportion, not be found within the confidence interval?

Answer 1

http://www.google.com/search?client=safari&rls=en&q=confidence+intervals&ie=UTF-8&oe=UTF-8

In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.

Answer 2

A confidence interval for the mean is a range ìlower < ì <ìupper where the lower bound is the smallest value of ì that we expect and the upper bound is the largest value of ì that we expect”(Doane-Seward,2007).
“If we wanted a narrower interval(i.e. more precision) we could either increase the sample size or lower the confidence level.”
5% the mean(population proportion) will not be found within the confidence interval.