### 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.**

Upon successful completion of this unit, you will be able to:

- explain the importance of statistics to business;
- explain the differences between quantitative and qualitative data, and identify examples of each type of data;
- define and apply the following terms: data sets, mean, median, mode, standard deviation, variance, population and sample;
- summarize and interpret data in a tabular format using frequency distributions and visually with histograms; and
- explain how to use a spreadsheet to describe data sets, create frequency tables, and draw histograms, as well as perform these tasks.

- explain the importance of statistics to business;

### 1.1: Why Do We Need to Study Statistical Analysis as Part of a Business Program?

- Read this article about the different ways that statistics are used in business, and why it is essential that decision-makers have the tools to analyze data as part of their skill set.

### 1.2: Measuring Data

This article introduces how we present a summary of data through graphs, tables, and numerical measures such as the average. This will be helpful in terms of analyzing business data in a simple way with the help of the widely-used methods in statistical analysis.

Watch the first video from 1:03:00 to the end, and the second video until 54:00. These videos explain the foundations of statistics, what data is, and the various types of data we'll be exploring.

### 1.3: Measures of Spread and Data

These videos explain the difference between the variance of a population of a sample, how to estimate the variance of a population based on a sample, and how to find the standard deviation and why it is important.

Read chapter 2, which discusses how to describe locations within a sample, and how to analyze data from a sample. Make sure you read the introduction as well as sections 2.1 through 2.7. Be sure to attempt the practice problems and homework at the end of each section.

If you would prefer to download this textbook, you may do so here.

### 1.4: Spreadsheet Exercises: Measures of Central Tendency and Spread

This section explores the measures of central tendency: mode, median, mean and midrange. It shows you the commands for computing these metrics using a spreadsheet program and it gives you the correct format for entering those commands into the spreadsheet program.

Attempt these questions, which will give you a chance to practice the materials covered in this subunit. You may wish to use a spreadsheet program, like Microsoft Excel, OpenOffice, or Google Sheets to perform calculations on the provided datasets.

### 1.5: Spreadsheet Exercises: Graphs of Histograms and Frequency Tables

Read this section.

Read this section. Note that the instructions given in the text are for version 2.x of OpenOffice. If you have 3.x, some steps are slightly different; you may need to consult the help documents.

### Unit 1 Problem Set and Assessment

For this assessment, do problems 3, 5, 17, and 24–30. Some of these problems don't include solutions, so only do the ones that have solutions. To see a problem solution, click "Show Solution" beneath the problem.

Take this assessment to see how well you understood this unit.

- This assessment
**does not count towards your grade**. It is just for practice! - You will see the correct answers when you submit your answers. Use this to help you study for the final exam!
- You can take this assessment as many times as you want, whenever you want.

- This assessment