Business Statistics For Dummies, 2nd Edition

Chapter 18

(Almost) Ten Key Categories of Formulas for Business Statistics

IN THIS CHAPTER

Keeping the most important statistical concepts fresh in your memory

Seeing how key statistical formulas are related

This chapter provides a brief overview of many key formulas discussed in the book. Think of this chapter as a a handy reference guide so that you can quickly find the formulas that you need without having to search through the entire book.

Summary Measures of a Population or a Sample

Summary measures are used to describe key properties of a sample or a population. These measures can be classified as:

• Measures of central tendency identify the center of a data set. Three of the most widely used measures of central tendency are the mean, median, and mode.
  • The mean is another word for average.
  • The median is a value that divides a sample or a population in half: Half of the elements in the data are less than or equal to the median, and half of the elements in the data are greater than or equal to the median.
  • The mode is the most frequently occurring value in a sample or a population.
• Measures of dispersion are used to measure how spread out, or disperse, are the values of a sample or a population. Some of the most important measures of dispersion are the variance, standard ...