https://www.youtube.com/watch?v=yyal_Kycx4c&list=PLZBQuJsCnFA6oaVR7Yx2P4rCQ0EzO9lH2

This is a common request, so I made these videos. Unlike with my other topics, where you may only need to watch one or two videos before you get the point, I strongly recommend watching all eight videos if this is completely new information. [No ads, not for revenue, just to help out.]

To be completely prepared for these questions, you should have taken AP Statistics or an equivalent class. I do not cover everything that College Board may ask on these questions, but this is the eight questions on conclusions that College Board asked in the practice book/Khan practice tests.

Note: These are not a complete lesson in statistical sampling and interpretation of results, just an introduction so that you can avoid feeling lost on every question. I say, for example, "sample size is rarely a problem in a survey . . ." and later I say "population size is not an issue and a sample size of 110 is sufficient even for conclusions about the entire United States". This does not mean that surveys have no error and produce an exact answer, just that those inaccuracies do not make a survey flawed (from the perspective of a mathematician or an SAT question writer) or invalid. Unlike the other topics I have covered and those I plan to cover (eventually all the common SAT topics), I plan to revisit conclusions, critiques, and interpretations of surveys and experiments to add more information based on a couple of new issues that later SAT questions have emphasized. I just need more time to choose the right questions to cover on this topic.