A new Rasmussen poll released Monday places President Obama’s daily approval index at -19, a number that has been somewhat consistent in the past month, ranging between -17 to -24. The Rasmussen presidential approval index is derived by calculating the difference between percentages of Rasmussen polling respondents who state they “strongly approve” and “strongly disapprove” of the president. In the case of the most recent results, 20 percent of respondents indicated strong approval, and 39 percent indicated strong disapproval.
Rasmussen Presidential Approval Index: A Scientific Model?
Scott Rasmussen began using the strongly approve/strongly disapprove model to gauge public sentiment in 2008, differentiating his polling organization from others who were releasing daily tracking reports based on overall approval and disapproval figures. Several polling experts, including Mark Blumenthal of Pollster.com, and Prof. Alan Abramowitz of Emory University, have been critical of Rasmussen’s index. They argue that Rasmussen overlooks the opinions of those who do not hold strong opinions regarding the president: a group that is often credited with defining elections.
Critics also make the point that incumbents historically face more strong opposition than strong support, but their overall likability and re-election chances are not always affected. For example, former President George W. Bush won re-election in 2004, despite slightly more exit poll respondents stating they strongly disapproved of him than strongly approved. Since Rasmussen’s index is so new, it is not yet possible to determine accuracy by comparing its results to those from past presidential campaigns.
Rasmussen’s Defense of the Presidential Approval Index
Rasmussen defends his index by referring to it as a way to determine the intensity of public opinion. He states that this is significant, since it can also be used to predict voter turnout and general enthusiasm regarding upcoming elections. In a 2009 interview with Talking Points Memo, Rasmussen acknowledged that his index would not be as relevant in 2012 election polling, but stated he was interested in using the 2010 results to develop a scientific hypothesis regarding the index’s ability to predict midterm elections, which tend to involve more voters with strong political opinions. Rasmussen predicted a weak performance by Democrats in 2010 due to the growing intensity gap, and his prediction held true. However, Rasmussen has maintained the same method of calculating the approval index since the conclusion of the 2010 midterm elections, despite his acknowledgement that less intense voters will have a stronger impact on 2012 results.
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