ABM: Concepts and Practice · Part A: Statistics

Chapter 2: Averages and spread

One figure to stand for many, and a second to say how far the many stray from it: the pair behind every target, rate and risk number.

Buyers of the e-book, or of the print copy, which includes it, read the whole chapter. Everyone can read the free sample, pages 1 to 24 of the e-book.

In this chapter

• 2.1The arithmetic meanp. 17
• 2.2Median, quartiles and modep. 18
• 2.3Geometric and harmonic meansp. 19
• 2.4Measures of dispersionp. 20
• 2.5Skewness and kurtosisp. 21
• Exam traps and quick checksp. 22
• Practice: 16 questions in three roundsp. 23
• Answers, with every wrong option explainedp. 25
• Make it stickp. 27
• Chapter 2 on one pagep. 28

Corrections and updates

None for this chapter so far. Every correction to the book, and any rule that changes after its date, is listed on the errata page.