Why is Statistics Important Foundational Concepts

Consider This Marketing cheeseheads to residents of Ashland & Bayfield counties (in 1990) Need to know the mean age and percentage of males Foundations I

How Should You Proceed? Want to know the mean & percentage male for the entire population Is this possible or reasonable? The best we can do is look at a sample (i.e., a portion of the population) How do we do that? How are individuals selected? How many individuals should be selected? Foundations I

Complete the Class Exercise Foundations I

Summary – Principles Statistics helps with these issues We cannot “see” the entire population i.e., we must sample to learn Variability is everywhere among individuals – Natural Variability among summaries of samples – Sampling Variability Conclusions are uncertain because population is unknown and variability Statistics helps with these issues That is WHY you are here!!! Foundations I

Summary – Goals of Statistics Description / Summarization Distill large amounts of data into a few informative numerical or graphical summaries Inference Make conclusions about the entire population from information gathered from the individuals in a sample Foundations I