STA 261 Lecture Notes - Lecture 6: Unimodality, Sampling Distribution
Document Summary
Parameter- a numerical descriptive measure of a population. Statistic- a quantity computed from values in a sample. Sampling distribution of a stat- the probability dist. Of the statistic that contains all possible samples of a given size: describes the long run behavior of the statistic, all stats have sampling distributions. The goal in a statistical study is to learn about this population distribution from the sample distribution. The sample distribution or data distribution: consist of the sample data that you actually observe and analyze, w/ random samplings, it should roughly resemble the popn distribution. The sampling distribution: describes how a sample stat varies if random samples are repeatedly taken from the popn, sampling distributions often behave very differently than the population of sample distribution- remember the clt. Sampling distribution of x bar: let x bar be the mean of observations in srs of size n from a population with mean, u, and standard dev. , o.
