Obviously the stock story is not entirely about growth: human beings are very complex and their behavior cannot be reduced down to just one factor.

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The fact of the matter is, human behavior is too complicated to limit to just one simple factor or another.

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Age is one factor, says Wendy Moncur, a computer technology and human behavior expert at the University of Aberdeen who has been researching the digital afterlife concept.

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Orszag thinks that economics and medicine are both beginning to take into account a factor that had been left out of scientific models for years: human behavior.

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To describe the prevalence of binge drinking, the CDC analyzed data from its 2011 Behavioral Risk Factor Surveillance System, an annual telephone survey, and the national 2011 Youth Risk Behavior Survey, an anonymous questionnaire completed by high school students nationwide.

CNN: CDC: 1 in 5 high school girls binge drink