200% of Nothing: An Eye-Opening Tour through the Twists and Turns of Math Abuse and Innumeracy
If you know the difference between lies, damned lies, and statistics, give a copy of A.K. Dewdney's200% of Nothingto your friends to get them up to speed.  If you don't know the difference, consider this funny, engaging little book a crash course in numeracy, the mathematical equivalent of literacy. Opening with two chapters on the importance of this dying talent, Dewdney (formerlyScientific American's "Mathematical Recreations" writer) spooks the reader with real examples of government agencies, media outlets, and--of course--car salesmen deceiving their audiences with beguiling mathematical sleights of hand. It's all too easy for us to think we're immune to such tactics until we actually see them laid out for us in prose as clear and disarming as Dewdney's.  From these tactics he delves more deeply into practical examples of particular problems that often catch us unaware. Gambling, advertisements using bizarre-but-normal-looking charts, and bad science all come in for thorough examinations, and the reader is amazed and occasionally angered at the shamelessness of the purveyors of misleading statistics.  The book closes with two chapters designed to make readers "mathematically streetwise," with exercises to help you grasp ratios, very large and small numbers, and probabilities more intuitively.200% of Nothinginspires learning and makes it interesting--if you want to see through the fog of numbers surrounding politicians and advertisements, there's no better place to start.--Rob Lightner