Intro to Confidence Intervals

What Is A Confidence Interval?

This video gets the confidence ball rolling by explaining in normal English what the point of these crazy things is (hint: if you're majoring in anything besides math or physics, this is the most useful thing you've done in stats thus far). Also covered are the concept of margin of error, and how to spot a confidence interval problem.

What A Confidence Interval Does NOT Tell You

I normally steer clear of mathy topics, but this one seems to get hit by every teacher and book, so it's worth taking on. Specifically, what words are you allowed to use when describing confidence intervals, and what words will get you busted down to private.

Critical Z-Values In Confidence Intervals

This video introduces the concept of a critical value, and then goes through some of the most common ones that you'll see again and again in confidence interval problems: z-values for 90%, 95%, and 99% confidence intervals.