The Associated Press has released a survey, taken on May 5-9, 2011 to measure public approval of Obama after the killing of Osama bin Laden. The poll purports to show that the president’s job approval has soared to 60 percent. Don’t you believe it.
The AP sample contains twice as many Democrats as Republicans (35% Democrat vs. 18% Republican). While party identification is, itself, a variable to be determined by polling, the normal sample usually contains an approximately equal number of Democrats and Republicans. Lately, Republicans have actually been slightly in the plurality in most statistically valid samples.
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