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Behind the Numbers
Posted at 03:31 PM ET, 04/13/2010

Just what is the South?

For many - my grandmother included - the South is a state of mind, but for data analysts, firmer definition is required. Herein lies a challenge: just what states constitute the region again at the forefront of political discourse?

Notably, the Census, exit pollsters and the American National Election Study (NES) offer three different answers to this question.

Among these primary providers of population and political data, the narrowest definition of the South is included in the NES datasets. Here, the "political south," comprises the 11 states of the confederacy: Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas and Virginia.

The exit poll adds Kentucky and Oklahoma to the mix for a baker's dozen.

The U.S. Department of Commerce, Bureau of the Census then layers in Delaware, Washington D.C., Maryland and West Virginia, bringing the total to 17 (16 states plus the District of Columbia).

This Census definition is the one typically used by media and academic pollsters in their data presentations (such as today's Take), but it may help to ask. After all, there's a difference of more than 17 million people between the NES and Census definitions. In 2008, the Census region included more than 7 million more voters than did the one labeled as Southern by the NES.

In the case of the last presidential election, however, the definitions made little difference, with Barack Obama topping John McCain by a similar margin in each classification ... 53 to 46 percent in the NES South and the exit poll South and 52 to 47 percent in the Census South.

By  |  03:31 PM ET, 04/13/2010

Categories:  methodology

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