• ### Unit 1: Introduction to Statistical Analysis

Even if you haven't taken a statistics course before, you are already familiar with the fundamentals of statistics from your everyday life. For instance, you already know that the majority of adult males have the same shoe size (which is very close to the average size), and that there are a few adult males on both sides of the average who have smaller or larger shoe sizes. In statistics, we call this phenomenon the "normal distribution".

This unit will introduce you to statistical analysis and how it relates to business. For example, you may be interested in learning about the average price of a 50-inch TV by gathering price data from 30 different stores. You would then take your 30 prices and compute the average price. Given the fact that there are thousands of stores that are selling that particular product, the next question in statistics is: are you confident enough to say that your computed average is reflective of the real average that you would get if you looked at the price for that TV at every possible store?

You are probably familiar with the average of a data set. In this course, we will refer to what most people call the average as the "arithmetic mean". The average is actually any single value used to describe the middle of a data set. The most common averages used in statistics are the arithmetic mean, the median, and the mode. Each describes the middle of a dataset in different ways. The median is the numeric value that separates the upper and lower half of a data set. The mean is the sum of all values divided by the number of values. The mode is the most common value within the dataset.

In many instances, the median and the mean are similar, but we will also talk about many examples where it is not. The distinction between these kinds of summary statistics is important in business statistics. Understanding this vocabulary will be vital to your success in this course and in the business world.

Completing this unit should take you approximately 6 hours.