If a researcher aimed to understand American attitudes about supersized soda bans, she would be foolish to limit her study to residents of New York City. Michael Bloomberg, the former mayor of the Big Apple, called for a ban on the sale of supersized sugary drinks in 2012. The controversial law probably affected attitudes about the issue, even though it was subsequently struck down. Thus, the people of New York City do not constitute a representative sample.
Ap Photo/Kathy Willens