A crash course in understanding numbersIn the 35 years since marijuana laws stopped being enforced in California, the number of marijuana smokers has doubled every year. Really? A Field Guide to Lies and Statistics. By Daniel Levitin. Dutton; 292 pages; $28. Viking; £14.99. PEOPLE take in five times as much information each day as they did in the mid-1980s. With all these data sloshing around it i
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