MATH 11 Lecture Notes - Lecture 15: Esci, Sampling Distribution, Statistical Parameter
Document Summary
5/10/17 lecture notes (15) ch 17 sampling distributions. The two most common parameters we gather on populations are: proportions (eg. % of people that go to college, % of people who are lgbt, means( eg. average weight of us men, mean sat score of ucsd students) When the populations are big, we must draw a (random) sample and estimate these parameters using statistics. Because of randomness, there is variation in this statistic (eq 3 polls for a political candidate might show 53%, 49% and 52. 1% support) We want to understand and visually display this variation. The different results we get from the various sample means appear to follow a normal model. Esci: excel spreadsheets by statistician geoff cummings to explore and confidence intervals (free download online, must enable excel macros to use) As the picture suggests, the center of the sample distribution is also at (no new letter needed) Finally, the sampling distribution is a normal curve.
