At halftime of the 1981 Super Bowl, the Joseph Schlitz Brewing Co. took what appeared to be a $1.7 million gamble when it put its lowly namesake swill up against Michelob in a blind taste test on live television. Terrible idea, right? Not so fast. The marketing department made sure that all 100 of the test’s participants were affirmed Michelob drinkers, which means that even if only 25 of them jumped ship, Schlitz could later tout “One in 4 Michelob drinkers prefers Schlitz.”

But what if Michelob swept the field? As Charles Wheelan explains in his brilliant, funny new book, Schlitz had figured out that it was probably more likely that an asteroid would’ve passed through one of the Louisiana Superdome’s uprights.

“There are two important lessons here: probability is a remarkably powerful tool, and many leading beers in the 1980s were indistinguishable from one another,” Wheelan writes.

Naked Statistics focuses on that lesson and others like it to demonstrate how the field of statistics can inform and improve the decisions we make about issues that arise in our daily lives.

Should you buy AppleCare on your new iPhone 5? Depends how wealthy you are. The numbers say you should “insure yourself against any adverse contingency that you cannot comfortably afford to withstand,” Wheelan writes. “Ironically, someone as rich as Warren Buffett can save money by not purchasing car insurance, homeowner’s insurance, or even health insurance because he can afford whatever bad things might happen to him.”

The best math teacher you never had, Wheelan isn’t out to hammer anyone with technical stuff, so most of the tricky math is relegated to appendices. This wise move prevents the author’s droll voice from being lost amid figures and equations.

Naked Statistics poses five specific questions in its conclusion that statistics can help answer, including “What is the Future of Football?” and “Who Gets to Know What About You?,” but the book is filled with practical lessons, like how to judge the validity of polls, why you should never buy a lottery ticket, and how to keep an eye out for red flags in public statements.

Wheelan, who calls statistics a “high caliber weapon,” points to the complex moral and ethical issues that can arise in the field. A statistical model exacerbated the 2008 financial crisis, and hospitals have graded doctors based on the mortality rate of patients, in which case the best way to improve their score was by “refusing to operate on the sickest patients.” He also touches on racial profiling. “It would be naive to think that gender, age, race, ethnicity, religion, and country of origin collectively tell us nothing about anything related to law enforcement,” he writes.

“For all the elegance and precision of probability, there is no substitute for thinking about what calculations we are doing and why we are doing them.”

John Wilwol reviewed this book for The San Francisco Chronicle.